diff --git a/crates/skate-core/src/physics/board_runtime.rs b/crates/skate-core/src/physics/board_runtime.rs
index 92a3ee66..f63de2f3 100644
--- a/crates/skate-core/src/physics/board_runtime.rs
+++ b/crates/skate-core/src/physics/board_runtime.rs
@@ -97,9 +97,13 @@ impl BoardRuntime {
         }
     }
 
-    pub fn collision_group(&self) -> u32 { self.collision_group }
+    pub fn collision_group(&self) -> u32 {
+        self.collision_group
+    }
     ///All seven native board parts share the current assembly group.
-    pub fn set_collision_group(&mut self, group: u32) { self.collision_group = group }
+    pub fn set_collision_group(&mut self, group: u32) {
+        self.collision_group = group
+    }
 
     pub fn bodies(&self) -> &[BodySnapshot; BODY_COUNT] {
         &self.bodies
@@ -142,9 +146,8 @@ impl BoardRuntime {
             body.rates.angular_velocity = Vector3::ZERO;
             body.rates.force_acceleration = gravity;
             body.rates.torque_acceleration = Vector3::ZERO;
-            body.rates.world_inverse_inertia = world_inverse_inertia(
-                body.rates.basis, body.inertia.inverse_tensor,
-            );
+            body.rates.world_inverse_inertia =
+                world_inverse_inertia(body.rates.basis, body.inertia.inverse_tensor);
         }
         copy_pose(&hook, &mut self.hook.body.rates);
         self.forces.clear();
@@ -263,6 +266,30 @@ impl BoardRuntime {
         set_part_transform(&mut part, pose_words(requested));
         copy_pose(&part, &mut self.hook.body.rates);
     }
+    ///82C0B2C8, used by board retrieval and hiding. Changes live part poses
+    ///without Reset's rate, contact-history, or force-queue clearing.
+    pub fn set_transform(&mut self, requested: RetailAffineTransform) {
+        let poses = self.part_transforms();
+        let mut parts = core::array::from_fn(|i| PartPose {
+            transform: pose_words(poses[i]),
+            local_mass_frame: Some(mass_frame_words(self.mass_frames[i])),
+            body: Some(body_pose_words(self.bodies[i].rates)),
+            inertia: Some(inertia_words(self.bodies[i].inertia)),
+        });
+        let mut hook = PartPose {
+            transform: pose_words(self.hook_transform()),
+            local_mass_frame: None,
+            body: Some(body_pose_words(self.hook.body.rates)),
+            inertia: None,
+        };
+        set_board_transform(&mut parts, &mut hook, pose_words(requested));
+        for (body, part) in self.bodies.iter_mut().zip(&parts) {
+            copy_pose(part, &mut body.rates);
+            body.rates.world_inverse_inertia =
+                world_inverse_inertia(body.rates.basis, body.inertia.inverse_tensor);
+        }
+        copy_pose(&hook, &mut self.hook.body.rates);
+    }
 }
 
 const ZERO_INERTIA: RetailInertiaDynamics = RetailInertiaDynamics {
diff --git a/crates/skate-core/src/physics/deck_angular_correction.rs b/crates/skate-core/src/physics/deck_angular_correction.rs
index 1428f6ff..f5a6b35d 100644
--- a/crates/skate-core/src/physics/deck_angular_correction.rs
+++ b/crates/skate-core/src/physics/deck_angular_correction.rs
@@ -10,6 +10,20 @@ use crate::math::{Basis3, Vector3};
 const STEP: f32 = f32::from_bits(0x3c88_8889);
 const NORMAL_MINIMUM: f32 = f32::from_bits(0x3586_37bd); //82F826F8 ->830BD350.
 
+///82C07328 subtracts the current angular displacement along the requested
+///axis, without07000's directional clamps, then performs the same tensor and
+///fixed-step conversion as075B8. The thrown-board controller calls this leaf.
+pub fn apply_axis_displacement(body: &mut RetailBodyRates, requested: Vector3) {
+    let squared = dot(requested, requested);
+    let inverse = inverse_length_squared(squared, 2);
+    let length = if squared == 0.0 { 0.0 } else { squared * inverse };
+    let direction = if length > NORMAL_MINIMUM {
+        scale(requested, inverse)
+    } else { Vector3::ZERO };
+    let existing = scale(direction, dot(direction, scale(body.angular_velocity, STEP)));
+    apply_angular_displacement(body, subtract(requested, existing));
+}
+
 /// 82C07000 first limits the requested angular displacement against the
 /// displacement already supplied by angular velocity along that same axis.
 pub fn apply_limited_displacement(body: &mut RetailBodyRates, requested: Vector3) {
@@ -130,6 +144,21 @@ mod tests {
         }
     }
     #[test]
+    fn thrown_board_correction_brakes_axis_overshoot_without_touching_other_motion() {
+        let mut state = body();
+        state.angular_velocity = Vector3::new(4., 3., 5.);
+        apply_axis_displacement(&mut state, Vector3::new(0., 0.02, 0.));
+        assert!((state.torque_acceleration.y + 108.).abs() < 0.0001);
+        assert!(state.torque_acceleration.x.abs() < 0.0001);
+        assert!(state.torque_acceleration.z.abs() < 0.0001);
+        assert_eq!(state.angular_velocity, Vector3::new(4., 3., 5.));
+        assert_eq!(state.cool_down, 0);
+        let mut reverse = body();
+        reverse.angular_velocity = Vector3::new(0., -3., 0.);
+        apply_axis_displacement(&mut reverse, Vector3::new(0., 0.02, 0.));
+        assert!((reverse.torque_acceleration.y - 252.).abs() < 0.0001);
+    }
+    #[test]
     fn correction_enters_accumulator_and_respects_existing_angular_motion() {
         let request = Vector3::new(0.02, 0.01, -0.03);
         let mut state = body();
diff --git a/crates/skate-core/src/physics/skateboard_controller.rs b/crates/skate-core/src/physics/skateboard_controller.rs
index a76d3433..fbbd790c 100644
--- a/crates/skate-core/src/physics/skateboard_controller.rs
+++ b/crates/skate-core/src/physics/skateboard_controller.rs
@@ -33,7 +33,7 @@ impl SkateboardController {
         let previous = self.fields.state_448;
         self.fields.word_444 = 0;
         if previous != 0 {
-            actions.let_go_of_skateboard();
+            actions.let_go_of_skateboard(&mut self.fields);
             self.fields.state_448 = 0;
         }
         self.fields.system_on_452 = false;
diff --git a/crates/skate-core/src/physics/tests/board_runtime.rs b/crates/skate-core/src/physics/tests/board_runtime.rs
index 1e269445..dde90a91 100644
--- a/crates/skate-core/src/physics/tests/board_runtime.rs
+++ b/crates/skate-core/src/physics/tests/board_runtime.rs
@@ -59,6 +59,43 @@ fn close(actual: Vector3, expected: Vector3) {
     );
 }
 
+#[test]
+fn moving_board_transform_preserves_rates_and_pending_forces() {
+    let mut board = runtime(Vector3::new(0., -9.8, 0.), BoardMotion::Active);
+    for (i, body) in board.bodies_mut().iter_mut().enumerate() {
+        body.rates.linear_velocity = Vector3::new(i as f32, 2., 3.);
+        body.rates.angular_velocity = Vector3::new(1., i as f32, 2.);
+        body.rates.force_acceleration = Vector3::new(5., 6., 7.);
+        body.rates.torque_acceleration = Vector3::new(8., 9., 10.);
+    }
+    let before = *board.bodies();
+    let parts = board.part_transforms();
+    let delta = Vector3::new(4., 5., 6.);
+    let mut target = parts[BodyId::Deck.index()];
+    target.translation = delta;
+    board.set_transform(target);
+    for (i, body) in board.bodies().iter().enumerate() {
+        close(body.rates.linear_velocity, before[i].rates.linear_velocity);
+        close(
+            body.rates.angular_velocity,
+            before[i].rates.angular_velocity,
+        );
+        close(
+            body.rates.force_acceleration,
+            before[i].rates.force_acceleration,
+        );
+        close(
+            body.rates.torque_acceleration,
+            before[i].rates.torque_acceleration,
+        );
+        let p = parts[i].translation;
+        close(
+            board.part_transforms()[i].translation,
+            Vector3::new(p.x + delta.x, p.y + delta.y, p.z + delta.z),
+        );
+    }
+}
+
 #[test]
 fn spawn_preserves_each_mass_frame_and_keeps_the_hook_separate() {
     let mut data = masses();
diff --git a/crates/skate-core/src/player/input_phase/types.rs b/crates/skate-core/src/player/input_phase/types.rs
index 06e9bd99..1e3c6722 100644
--- a/crates/skate-core/src/player/input_phase/types.rs
+++ b/crates/skate-core/src/player/input_phase/types.rs
@@ -118,8 +118,14 @@ pub struct GrindOutputFields {
 #[derive(Clone, Copy, Debug, Default, PartialEq)]
 pub struct OffBoardOutputFields {
     pub scalar_32: f32,
+    pub board_angle_36: f32,
+    pub board_angle_40: f32,
     pub flag_304: u8,
     pub flag_311: u8,
+    pub free_board_312: u8,
+    pub returning_board_313: u8,
+    pub hidden_board_321: u8,
+    pub board_request_324: u8,
     pub flag_314: u8,
     pub flag_315: u8,
     pub flag_316: u8,
diff --git a/crates/skate-core/src/player/lifecycle.rs b/crates/skate-core/src/player/lifecycle.rs
index 05033b17..3fb7adb7 100644
--- a/crates/skate-core/src/player/lifecycle.rs
+++ b/crates/skate-core/src/player/lifecycle.rs
@@ -79,8 +79,8 @@ pub struct StateChangeData {
 /// implementations are `HoldSkateboard` `0x82D75370` and
 /// `LetGoOfSkateboard` `0x82D75440`; this lifecycle never replaces them.
 pub trait SkateboardControllerActions {
-    fn hold_skateboard(&mut self);
-    fn let_go_of_skateboard(&mut self);
+    fn hold_skateboard(&mut self, _fields: &mut SkateboardControllerFields);
+    fn let_go_of_skateboard(&mut self, _fields: &mut SkateboardControllerFields);
 }
 
 /// Context supplied to an owned state's Enter or Exit implementation.
@@ -196,11 +196,11 @@ fn prepare_skateboard_controller<C: SkateboardControllerActions>(
     controller.word_444 = 0;
     if processed_flags_2480 & (0x80 | 0x100) != 0 {
         if controller.state_448 != 2 {
-            actions.let_go_of_skateboard();
+            actions.let_go_of_skateboard(controller);
             controller.state_448 = 2;
         }
     } else if controller.state_448 != 1 {
-        actions.hold_skateboard();
+        actions.hold_skateboard(controller);
         controller.state_448 = 1;
     }
     controller.system_on_452 = true;
@@ -218,7 +218,7 @@ fn stop_skateboard_controller<C: SkateboardControllerActions>(
     let previous_state = controller.state_448;
     controller.word_444 = 0;
     if previous_state != 0 {
-        actions.let_go_of_skateboard();
+        actions.let_go_of_skateboard(controller);
         controller.state_448 = 0;
     }
     controller.system_on_452 = false;
diff --git a/crates/skate-core/src/player/tests/lifecycle.rs b/crates/skate-core/src/player/tests/lifecycle.rs
index 0c05560f..bcb5c936 100644
--- a/crates/skate-core/src/player/tests/lifecycle.rs
+++ b/crates/skate-core/src/player/tests/lifecycle.rs
@@ -37,11 +37,11 @@ impl PhysicalStateCalls for SharedRecorder {
 }
 
 impl SkateboardControllerActions for SharedRecorder {
-    fn hold_skateboard(&mut self) {
+    fn hold_skateboard(&mut self, _fields: &mut SkateboardControllerFields) {
         self.events.borrow_mut().push(Event::Hold);
     }
 
-    fn let_go_of_skateboard(&mut self) {
+    fn let_go_of_skateboard(&mut self, _fields: &mut SkateboardControllerFields) {
         self.events.borrow_mut().push(Event::LetGo);
     }
 }
@@ -62,11 +62,11 @@ impl PhysicalStateCalls for Recorder {
 }
 
 impl SkateboardControllerActions for Recorder {
-    fn hold_skateboard(&mut self) {
+    fn hold_skateboard(&mut self, _fields: &mut SkateboardControllerFields) {
         self.events.push(Event::Hold);
     }
 
-    fn let_go_of_skateboard(&mut self) {
+    fn let_go_of_skateboard(&mut self, _fields: &mut SkateboardControllerFields) {
         self.events.push(Event::LetGo);
     }
 }
@@ -97,6 +97,41 @@ fn seeded_data() -> StateChangeData {
     }
 }
 
+#[test]
+fn release_callback_retains_its_throw_countdown_through_state_publication() {
+    struct Throw;
+    impl SkateboardControllerActions for Throw {
+        fn hold_skateboard(&mut self, _: &mut SkateboardControllerFields) {
+            panic!("unexpected hold");
+        }
+        fn let_go_of_skateboard(&mut self, fields: &mut SkateboardControllerFields) {
+            assert_eq!(fields.word_444, 0);
+            fields.word_444 = 8;
+        }
+    }
+    let mut data = seeded_data();
+    data.skateboard_controller = SkateboardControllerFields {
+        word_444: 123,
+        state_448: 1,
+        system_on_452: true,
+    };
+    let mut states = Recorder {
+        reported_type: PhysicalStateId::BipedGround,
+        events: vec![],
+    };
+    PhysicalPlayerStateLifecycle::new(PhysicalStateId::BipedGround)
+        .set_physics_state(
+            PhysicalStateId::PhysicsGround as u32,
+            &mut data,
+            &mut states,
+            &mut Throw,
+        )
+        .unwrap();
+    assert_eq!(data.skateboard_controller.word_444, 8);
+    assert_eq!(data.skateboard_controller.state_448, 0);
+    assert!(!data.skateboard_controller.system_on_452);
+}
+
 fn recorder(reported_type: PhysicalStateId) -> Recorder {
     Recorder {
         reported_type,
diff --git a/crates/skate-core/src/player/tests/logic.rs b/crates/skate-core/src/player/tests/logic.rs
index 3929ed5d..61740dcd 100644
--- a/crates/skate-core/src/player/tests/logic.rs
+++ b/crates/skate-core/src/player/tests/logic.rs
@@ -43,8 +43,8 @@ impl PhysicalStateCalls for States {
 struct Controller;
 
 impl SkateboardControllerActions for Controller {
-    fn hold_skateboard(&mut self) {}
-    fn let_go_of_skateboard(&mut self) {}
+    fn hold_skateboard(&mut self, _fields: &mut SkateboardControllerFields) {}
+    fn let_go_of_skateboard(&mut self, _fields: &mut SkateboardControllerFields) {}
 }
 
 fn input() -> StateSelectionInput {
diff --git a/crates/skate-game/src/physics.rs b/crates/skate-game/src/physics.rs
index 577ac132..2033011f 100644
--- a/crates/skate-game/src/physics.rs
+++ b/crates/skate-game/src/physics.rs
@@ -276,6 +276,10 @@ impl GamePhysics {
             self.processed_flags_2468,
             self.settings.step.simulation.time_step,
         )?;
+        offboard::board_effects::classify_alignment(
+            &skater.offboard.board_policy,
+            &mut self.riding.ground,
+        );
         let partial = skateboard_controller::partial_request(
             &skater.skateboard_controller,
             &self.riding.ground,
diff --git a/crates/skate-game/src/physics/frame.rs b/crates/skate-game/src/physics/frame.rs
index 5c5a8957..41557863 100644
--- a/crates/skate-game/src/physics/frame.rs
+++ b/crates/skate-game/src/physics/frame.rs
@@ -123,6 +123,7 @@ pub(super) fn advance(
         }
         state => return Err(format!("Selected {state:?} requires its physical update")),
     }
+    super::offboard::possession::update(physics, skater)?;
     // Source State82DB6120 submits the queue once, then advances state time.
     // BoardRuntime applies that same queue during its shared solve.
     skater.player_input.player.state_timer_1344 += skater.player_input.processed.timestep_2604;
diff --git a/crates/skate-game/src/physics/offboard/board_effects.rs b/crates/skate-game/src/physics/offboard/board_effects.rs
new file mode 100644
index 00000000..5260d889
--- /dev/null
+++ b/crates/skate-game/src/physics/offboard/board_effects.rs
@@ -0,0 +1,142 @@
+//! Board-controller effects applied to the existing board and hook bodies.
+use skate_core::{
+    math::{Basis3, Vector3},
+    physics::{board::BodyId, board_runtime::BoardRuntime, drive_frames::RetailAffineTransform},
+    player::offboard::board_possession::{
+        Frame, Vector,
+        lifecycle::{Alignment, Effects},
+    },
+};
+
+pub(crate) struct Policy {
+    pub volumes_enabled: bool,
+    pub released: bool,
+    pub alignment: Option<Alignment>,
+}
+impl Default for Policy {
+    fn default() -> Self {
+        Self {
+            volumes_enabled: true,
+            released: false,
+            alignment: None,
+        }
+    }
+}
+pub(crate) struct BoardEffects<'a> {
+    pub board: &'a mut BoardRuntime,
+    pub animated: &'a mut u8,
+    pub policy: &'a mut Policy,
+    pub standard_deck_drag: f32,
+    pub timestep: f32,
+}
+fn xyz(v: Vector) -> Vector3 {
+    Vector3::new(v[0], v[1], v[2])
+}
+fn transform(f: Frame) -> RetailAffineTransform {
+    RetailAffineTransform {
+        basis: Basis3 {
+            columns: std::array::from_fn(|i| [f[i][0], f[i][1], f[i][2]]),
+        },
+        translation: xyz(f[3]),
+    }
+}
+impl Effects for BoardEffects<'_> {
+    fn enable_animation_soft(&mut self) {
+        self.board
+            .hook_mut()
+            .drive
+            .enable_animation_soft(self.animated);
+    }
+    fn enable_animation_angular_only(&mut self) {
+        self.board
+            .hook_mut()
+            .drive
+            .enable_angular_only(self.animated);
+    }
+    fn disable_animation(&mut self) {
+        self.board.hook_mut().drive.disable_animation(self.animated);
+    }
+    fn disable_linear_drive(&mut self) {
+        self.board.hook_mut().drive.disable_linear();
+    }
+    fn standard_board(&mut self) {
+        self.policy.released = false;
+        self.board.set_collision_group(4);
+        self.board.bodies_mut()[BodyId::Deck.index()]
+            .inertia
+            .angular_drag = self.standard_deck_drag;
+        self.policy.volumes_enabled = true;
+    }
+    fn released_board(&mut self) {
+        self.policy.released = true;
+        self.board.bodies_mut()[BodyId::Deck.index()]
+            .inertia
+            .angular_drag = f32::from_bits(0x416f_ffff);
+        self.board.set_collision_group(7);
+        self.policy.volumes_enabled = true;
+    }
+    fn collision_volumes(&mut self, enabled: bool) {
+        self.policy.volumes_enabled = enabled;
+    }
+    fn clear_alignment(&mut self) {
+        self.policy.alignment = None;
+    }
+    fn alignment(&mut self, value: Alignment) {
+        self.policy.alignment = Some(value);
+    }
+    fn velocity(&mut self, value: Vector) {
+        for body in self.board.bodies_mut() {
+            body.rates.linear_velocity = xyz(value);
+        }
+    }
+    fn position(&mut self, value: Vector) {
+        let mut target = self.board.part_transforms()[BodyId::Deck.index()];
+        target.translation = xyz(value);
+        self.board.set_transform(target);
+    }
+    fn hook_frame(&mut self, value: Frame) {
+        self.board.set_hook_transform(transform(value));
+    }
+    fn target_position_velocity(&mut self, value: Vector) {
+        //82C04270 reads Body+16 (mass-frame position), not GetPartTransform.
+        let origin = self.board.bodies()[BodyId::Deck.index()].rates.position;
+        let frequency = 1.0 / self.timestep;
+        self.velocity([
+            (value[0] - origin.x) * frequency,
+            (value[1] - origin.y) * frequency,
+            (value[2] - origin.z) * frequency,
+            0.,
+        ]);
+    }
+    fn torque(&mut self, value: Vector) {
+        //750F0 passes all three767D0 outputs to07328. They are requested
+        //angular displacements, not direct torques or inverse-inertia products.
+        skate_core::physics::deck_angular_correction::apply_axis_displacement(
+            &mut self.board.bodies_mut()[BodyId::Deck.index()].rates,
+            xyz(value),
+        );
+    }
+}
+
+///82C08370..8428 classifies retained per-part normals against the controller's
+///two directions. This is a release observation, not an extra force or joint.
+pub(crate) fn classify_alignment(
+    policy: &Policy,
+    ground: &mut skate_core::physics::board_ground::BoardGroundState,
+) {
+    let Some(a) = policy.alignment else {
+        return;
+    };
+    for part in &ground.parts {
+        if !part.in_contact {
+            continue;
+        }
+        let normal = [part.normal.x, part.normal.y, part.normal.z, 0.];
+        if [a.first_1008, a.second_1024].into_iter().any(|direction| {
+            (normal[0] * -direction[0] + normal[1] * -direction[1]) + normal[2] * -direction[2]
+                > a.factor_1040
+        }) {
+            ground.collision_flags |= 0x0400_0000;
+        }
+    }
+}
diff --git a/crates/skate-game/src/physics/offboard/hand_drives.rs b/crates/skate-game/src/physics/offboard/hand_drives.rs
new file mode 100644
index 00000000..f5a3999a
--- /dev/null
+++ b/crates/skate-game/src/physics/offboard/hand_drives.rs
@@ -0,0 +1,153 @@
+//! Native SkateboardController drives82D74FD8 /82D751D8 in the shared island.
+//! Factory82AE64F8 stores argument5 at drive16 (A), argument4 at20 (B):
+//! hand bodies3/7 are A and the deck is B, despite the factory argument order.
+use skate_core::{
+    math::{Basis3, Vector3},
+    physics::{
+        assembly::BodySnapshot,
+        board::BodyId,
+        board_step::ATTACHED_REACTION_BASE,
+        drive_frames::{RetailDriveFrame, RetailDriveFrames, retail_quaternion_from_basis},
+        drive_parameters::{RetailDriveDynamics, RetailDriveParams, RetailDriveType},
+        drive_solver::{RetailDriveBodyState, RetailDriveRows, build_drive_rows},
+        rigid_body::pack_world_inverse_inertia,
+        skeleton_body::prepare_bone_drive_frames,
+    },
+    player::offboard::board_possession::{Frame, State},
+};
+
+pub(crate) fn append(
+    rows: &mut Vec<RetailDriveRows>,
+    state: &State,
+    board: &[BodySnapshot; 7],
+    skeleton: &[BodySnapshot; 26],
+    dt: f32,
+) {
+    for (hand, part) in [3, 7].into_iter().enumerate() {
+        let drive = state.hands[hand];
+        let a = skeleton[part];
+        let b = board[BodyId::Deck.index()];
+        if (a.state_flags | b.state_flags) & 4 == 0 {
+            continue;
+        }
+        let parameters = |words: [u32; 4]| RetailDriveParams {
+            spring_or_max_velocity: f32::from_bits(words[0]),
+            damping: f32::from_bits(words[1]),
+            max_strength: f32::from_bits(words[2]),
+            drive_type: match words[3] {
+                1 => RetailDriveType::SoftDrive,
+                2 => RetailDriveType::HardDrive,
+                _ => RetailDriveType::NoDrive,
+            },
+        };
+        rows.push(build_drive_rows(
+            body(a, ATTACHED_REACTION_BASE + part),
+            body(b, BodyId::Deck.index()),
+            prepare_bone_drive_frames(RetailDriveFrames {
+                body_a: frame(drive.child),
+                body_b: frame(drive.parent),
+            }),
+            RetailDriveDynamics {
+                linear: parameters(drive.dynamics[0]),
+                angular: parameters(drive.dynamics[1]),
+            },
+            dt,
+        ));
+    }
+}
+fn frame(f: Frame) -> RetailDriveFrame {
+    RetailDriveFrame {
+        orientation: retail_quaternion_from_basis(Basis3 {
+            columns: std::array::from_fn(|i| [f[i][0], f[i][1], f[i][2]]),
+        }),
+        translation: Vector3::new(f[3][0], f[3][1], f[3][2]),
+    }
+}
+fn body(b: BodySnapshot, index: usize) -> RetailDriveBodyState {
+    let r = b.rates;
+    RetailDriveBodyState {
+        reaction_index: index,
+        state: b.state_flags,
+        orientation: r.orientation,
+        basis: r.basis,
+        center_of_mass: r.position,
+        linear_velocity: r.linear_velocity,
+        angular_velocity: r.angular_velocity,
+        force_acceleration: r.force_acceleration,
+        torque_acceleration: r.torque_acceleration,
+        inverse_mass: b.inertia.inverse_mass,
+        world_inverse_inertia: pack_world_inverse_inertia(r.world_inverse_inertia),
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use skate_core::physics::{
+        drive_solver::solve_drive_rows,
+        rigid_body::{
+            RetailBodyRates, RetailInertiaDynamics, RetailQuaternion, RetailReactionCorrections,
+        },
+    };
+    fn active() -> BodySnapshot {
+        let basis = Basis3 {
+            columns: [[1., 0., 0.], [0., 1., 0.], [0., 0., 1.]],
+        };
+        BodySnapshot {
+            state_flags: 4,
+            rates: RetailBodyRates {
+                orientation: RetailQuaternion::IDENTITY,
+                basis,
+                world_inverse_inertia: basis,
+                position: Vector3::ZERO,
+                linear_velocity: Vector3::ZERO,
+                angular_velocity: Vector3::ZERO,
+                force_acceleration: Vector3::ZERO,
+                torque_acceleration: Vector3::ZERO,
+                kinetic_energy: 0.,
+                cool_down: 0,
+            },
+            inertia: RetailInertiaDynamics {
+                inverse_tensor: Vector3::new(1., 1., 1.),
+                inverse_mass: 1.,
+                spherical: 0.,
+                maximum_linear_velocity: 1000.,
+                maximum_angular_velocity: 1000.,
+                linear_drag: 0.,
+                angular_drag: 0.,
+            },
+        }
+    }
+    #[test]
+    fn held_hand_and_deck_exchange_reactions_and_release_removes_force() {
+        let board = [active(); 7];
+        let mut skeleton = [active(); 26];
+        skeleton[3].rates.position.x = 1.;
+        let mut state = State::default();
+        state.selected_hand_424 = 0;
+        state.hands[0].dynamics = [[0x4395ffff, 0, 0x468c9fff, 2]; 2];
+        let mut rows = Vec::new();
+        append(&mut rows, &state, &board, &skeleton, 1. / 60.);
+        let mut reactions = [RetailReactionCorrections::default(); 34];
+        solve_drive_rows(&mut rows, &mut reactions, 4);
+        let hand = reactions[ATTACHED_REACTION_BASE + 3].linear_displacement.x;
+        let deck = reactions[BodyId::Deck.index()].linear_displacement.x;
+        assert!(hand < 0. && deck > 0., "hand={hand}, deck={deck}");
+        assert!((hand + deck).abs() < 1e-6);
+        assert_eq!(
+            reactions[ATTACHED_REACTION_BASE + 7].linear_displacement,
+            Vector3::ZERO
+        );
+        state.disable_hand();
+        rows.clear();
+        append(&mut rows, &state, &board, &skeleton, 1. / 60.);
+        reactions.fill(RetailReactionCorrections::default());
+        solve_drive_rows(&mut rows, &mut reactions, 4);
+        assert!(
+            reactions
+                .iter()
+                .all(|r| r.linear_displacement == Vector3::ZERO
+                    && r.angular_displacement == Vector3::ZERO)
+        );
+    }
+}
diff --git a/crates/skate-game/src/physics/offboard/mod.rs b/crates/skate-game/src/physics/offboard/mod.rs
index 9f5569af..2a6b181d 100644
--- a/crates/skate-game/src/physics/offboard/mod.rs
+++ b/crates/skate-game/src/physics/offboard/mod.rs
@@ -1,8 +1,11 @@
 //! Off-board game adapters over the shared physical and scene owners.
+pub(crate) mod board_effects;
+pub(crate) mod contact_queries;
+pub(crate) mod ground_input;
 pub(crate) mod ground_query;
+pub(crate) mod hand_drives;
 pub(crate) mod pose_adjust;
+pub(crate) mod possession;
+pub(crate) mod runtime;
 pub(crate) mod settings;
 pub(crate) mod skeleton_ground;
-pub(crate) mod contact_queries;
-pub(crate) mod runtime;
-pub(crate) mod ground_input;
diff --git a/crates/skate-game/src/physics/offboard/possession.rs b/crates/skate-game/src/physics/offboard/possession.rs
new file mode 100644
index 00000000..d64f038d
--- /dev/null
+++ b/crates/skate-game/src/physics/offboard/possession.rs
@@ -0,0 +1,117 @@
+//! Native hand controller over the player's live pose and board observations.
+use crate::physics::{GamePhysics, SkaterRuntime};
+use skate_core::{
+    physics::{contact_feedback::choose_surface, skeleton_animation_record::compose_affine},
+    player::offboard::board_possession::{Processed, lifecycle::Observation},
+};
+
+pub(crate) struct Actions<'a> {
+    pub state: &'a mut skate_core::player::offboard::board_possession::State,
+    pub settings: &'a skate_core::player::offboard::board_possession::lifecycle::Settings,
+    pub observation: &'a Observation,
+    pub effects: super::board_effects::BoardEffects<'a>,
+}
+impl skate_core::player::lifecycle::SkateboardControllerActions for Actions<'_> {
+    fn hold_skateboard(
+        &mut self,
+        fields: &mut skate_core::player::lifecycle::SkateboardControllerFields,
+    ) {
+        self.state.hold(fields, self.observation, &mut self.effects);
+    }
+    fn let_go_of_skateboard(
+        &mut self,
+        fields: &mut skate_core::player::lifecycle::SkateboardControllerFields,
+    ) {
+        self.state
+            .let_go(fields, self.observation, self.settings, &mut self.effects);
+    }
+}
+
+pub(crate) fn observe(
+    physics: &GamePhysics,
+    skater: &SkaterRuntime,
+) -> Result<Observation, String> {
+    let p = &skater.player_input.processed;
+    let toolkit = skater
+        .player_input
+        .toolkit
+        .as_ref()
+        .ok_or("Board controller requires this update's board toolkit")?;
+    let roots = &skater.animated_skeleton.roots;
+    let frames = &skater.skeleton_input.drive_frames;
+    let physical_parts = skater.skeleton.part_transforms();
+    Ok(Observation {
+        processed: Processed {
+            board_frame_64: toolkit.deck,
+            player_frame_192: p
+                .effective_anim_transform_192
+                .map(|v| v.map(f32::from_bits)),
+            position_592: p.vectors_544_560_592_608[2].map(f32::from_bits),
+            velocity_912: p.vectors_880_896_912_928_944[2].map(f32::from_bits),
+            direction_400: p.vectors_400_416[0].map(f32::from_bits),
+            hide_direction_464: p.vectors_464_480_496_512_528[0].map(f32::from_bits),
+            flags_2476: p.flags_2476,
+            flags_2480: p.flags_2480,
+            flags_2488: p.flags_2488,
+        },
+        board_collision_flags_872: physics.riding.ground.collision_flags,
+        //82C08818 produces840 by voting the four retained wheel surfaces.
+        board_state_840: choose_surface(
+            physics.riding.wheel_lines.physics_surfaces,
+            std::array::from_fn(|i| physics.riding.ground.parts[i].in_contact),
+            physics.riding.ground.collision_flags & 0x0200_0000 != 0,
+        ),
+        hand_contacts: [3, 7].map(|i| skater.collision_feedback.current[i]),
+        physical_hand_positions: [3, 7].map(|i| physical_parts[i][3]),
+        animation_board_frame_12624: frames[0],
+        animation_hand_frames: [frames[3], frames[7]],
+        attachment_frame_0: compose_affine(&roots.animation_to_world, &frames[0]),
+    })
+}
+
+pub(crate) fn update(physics: &mut GamePhysics, skater: &mut SkaterRuntime) -> Result<(), String> {
+    if !skater.skateboard_controller.fields.system_on_452 {
+        return Ok(());
+    }
+    let observation = observe(physics, skater)?;
+    let offboard = &mut skater.offboard;
+    let mut effects = super::board_effects::BoardEffects {
+        board: &mut physics.board,
+        animated: &mut skater.ground_lifecycle.board_animated_290,
+        policy: &mut offboard.board_policy,
+        standard_deck_drag: offboard.standard_deck_drag,
+        timestep: skater.player_input.processed.timestep_2604,
+    };
+    offboard.possession.update(
+        &mut skater.skateboard_controller.fields,
+        &observation,
+        &offboard.possession_settings,
+        &mut effects,
+    );
+    Ok(())
+}
+
+pub(crate) fn publish(physics: &GamePhysics, skater: &mut SkaterRuntime) -> Result<(), String> {
+    let observation = observe(physics, skater)?;
+    let bone = compose_affine(
+        &skater.animated_skeleton.roots.animation_to_world,
+        &skater.skeleton_input.drive_frames[11],
+    );
+    let value = skate_core::player::offboard::board_possession::fill(
+        &skater.skateboard_controller.fields,
+        &skater.offboard.possession,
+        &observation.processed,
+        bone,
+    );
+    let output = &mut skater.player_input.physical.off_board;
+    output.board_angle_36 = value.angle_36;
+    output.board_angle_40 = value.angle_40;
+    output.flag_311 = u8::from(value.held_311);
+    output.free_board_312 = u8::from(value.free_312);
+    output.returning_board_313 = u8::from(value.returning_313);
+    output.hidden_board_321 = u8::from(value.hiding_321);
+    output.dropping_board_322 = u8::from(value.flag_322);
+    output.retrieving_board_323 = u8::from(value.flag_323);
+    output.board_request_324 = u8::from(value.flag_324);
+    Ok(())
+}
diff --git a/crates/skate-game/src/physics/offboard/runtime.rs b/crates/skate-game/src/physics/offboard/runtime.rs
index 1a8b645f..331ca803 100644
--- a/crates/skate-game/src/physics/offboard/runtime.rs
+++ b/crates/skate-game/src/physics/offboard/runtime.rs
@@ -10,6 +10,10 @@ use skate_core::point_graph::PointGraph;
 use skate_data::{animation_metadata::AnimationMetadata, collections::Collections};
 
 pub(crate) struct Runtime {
+    pub board_policy: super::board_effects::Policy,
+    pub standard_deck_drag: f32,
+    pub possession: skate_core::player::offboard::board_possession::State,
+    pub possession_settings: skate_core::player::offboard::board_possession::lifecycle::Settings,
     pub controller: Controller,
     pub ground: ground_entry::State,
     pub contacts: Toolkit,
@@ -136,6 +140,11 @@ impl Runtime {
     pub(crate) fn load(data: &Collections, metadata: &AnimationMetadata) -> Result<Self, String> {
         let settings = super::settings::Settings::load(data, metadata)?;
         Ok(Self {
+            board_policy: Default::default(),
+            standard_deck_drag: data.float("physicsdeck", "default", "DeckAngularDrag")?
+                * f32::from_bits(0x426f_ffff),
+            possession: Default::default(),
+            possession_settings: settings.possession,
             controller: Controller::new(settings.controller, settings.metrics),
             ground: Default::default(),
             contacts: Default::default(),
diff --git a/crates/skate-game/src/physics/offboard/settings.rs b/crates/skate-game/src/physics/offboard/settings.rs
index 7d6458c4..bf435340 100644
--- a/crates/skate-game/src/physics/offboard/settings.rs
+++ b/crates/skate-game/src/physics/offboard/settings.rs
@@ -2,6 +2,7 @@
 mod board;
 mod curves;
 mod metrics;
+mod possession;
 #[cfg(test)]
 mod tests;
 use skate_core::{
@@ -11,6 +12,7 @@ use skate_core::{
 use skate_data::{animation_metadata::AnimationMetadata, collections::Collections};
 
 pub(crate) struct Settings {
+    pub possession: skate_core::player::offboard::board_possession::lifecycle::Settings,
     pub controller: controller::Settings,
     pub board: skate_core::player::offboard::ground_sync::BoardSettings,
     pub metrics: [Option<controller::ClipMetric>; 3],
@@ -26,6 +28,7 @@ impl Settings {
         let biped = |name| curves::load::<8>(data, "physics_biped", name);
         let (sprint_blend, bounds) = biped("Hash_6B93C51256A30FB4")?;
         Ok(Self {
+            possession: possession::load(data)?,
             controller: controller::Settings {
                 movement_intent: movement_intent::Settings {
                     sprint_speed: curves::load::<4>(
diff --git a/crates/skate-game/src/physics/offboard/settings/possession.rs b/crates/skate-game/src/physics/offboard/settings/possession.rs
new file mode 100644
index 00000000..525d4344
--- /dev/null
+++ b/crates/skate-game/src/physics/offboard/settings/possession.rs
@@ -0,0 +1,24 @@
+//! Stock physics_skatecontroller/default data used by the board controller.
+use skate_core::player::offboard::board_possession::lifecycle::Settings;
+use skate_data::collections::Collections;
+pub(super) fn load(data: &Collections) -> Result<Settings, String> {
+    let float = |name| data.float("physics_skatecontroller", "default", name);
+    let curve = |name| super::curves::load::<8>(data, "physics_skatecontroller", name).map(|v| v.0);
+    Ok(Settings {
+        //75F00 reads893DA1B966231D76 for the hide trigger;75BB8 reads
+        //6CFF6F2C43F0AD41 for the hidden position. Lookup8 verifies both names.
+        hide_distance: float("MaxDistance")?,
+        hide_offset: float("DistanceToHideSkateboard")?,
+        return_distance: float("DistanceForBoardReturn")?,
+        mounted_return_distance: float("DistanceForMountedReturn")?,
+        mounting_time: float("MinTimeToRetrieveBoardWhileMounting")?,
+        retrieval_time: curve("RetrievalTimeVsDist")?,
+        retrieval_weight: curve("RetrievalSpeedCurve")?,
+        throw_pitch: float("ThrownSkateboardLaunchPitch")?,
+        throw_velocity: curve("ThrownSkateboardVelocity")?,
+        throw_target_pitch: float("ThrownSkateboardPitchTarget")?,
+        throw_pitch_scalar: float("ThrownSkateboardPitchScalar")?,
+        throw_roll_scalar: float("ThrownSkateboardRollScalar")?,
+        throw_yaw_scalar: float("ThrownSkateboardYawScalar")?,
+    })
+}
diff --git a/crates/skate-game/src/physics/offboard/settings/tests.rs b/crates/skate-game/src/physics/offboard/settings/tests.rs
index df156b07..7a9c2f9d 100644
--- a/crates/skate-game/src/physics/offboard/settings/tests.rs
+++ b/crates/skate-game/src/physics/offboard/settings/tests.rs
@@ -85,4 +85,7 @@ fn actual_stock_settings_and_metrics_load_together() {
     });
     assert!(speeds[0] > 0.0 && speeds[0] < speeds[1] && speeds[1] < speeds[2]);
     assert_eq!(settings.controller.movement_intent.sprint_time_cap, 4.0);
+    //Independent native lookup8 keys:893DA1B966231D76 /6CFF6F2C43F0AD41.
+    assert_eq!(settings.possession.hide_distance, 30.0);
+    assert_eq!(settings.possession.hide_offset, 1000.0);
 }
diff --git a/crates/skate-game/src/physics/offboard/skeleton_ground.rs b/crates/skate-game/src/physics/offboard/skeleton_ground.rs
index e32c1e4a..9c9452bf 100644
--- a/crates/skate-game/src/physics/offboard/skeleton_ground.rs
+++ b/crates/skate-game/src/physics/offboard/skeleton_ground.rs
@@ -25,6 +25,51 @@ pub(crate) struct ReckoningUpdate {
     pub forward: [f32; 4],
     pub blend: f32,
 }
+
+///Borrow the same bodies, IK, roots, collision feedback and camera reckoning as
+///the riding phases. Sync supplies the completed Biped job frame and COM.
+pub(crate) fn update(
+    physics: &mut crate::physics::GamePhysics,
+    skater: &mut crate::physics::SkaterRuntime,
+    frame: Transform,
+    centre_of_mass: [f32; 4],
+) -> Result<(), String> {
+    let collision = crate::physics::input_phase::collision(skater);
+    let flags = skater.player_input.processed.flags_2468;
+    let spin = skater.animation_input.extra.physical_body_spin;
+    let mut owners = SkeletonOwners {
+        animated: &mut skater.animated_skeleton,
+        body: &mut skater.skeleton,
+        drives: &mut skater.skeleton_drives,
+        ik: &mut skater.foot_ik,
+        animation_input: &mut skater.animation_input,
+        correction: &mut skater.skeleton_output.correction,
+        pose_errors: &mut skater.pose_errors,
+    };
+    skater.skeleton_input.update_biped_ground(
+        &mut skater.skeleton_air,
+        &mut physics.board,
+        Input {
+            world_frame: &frame,
+            centre_of_mass_1056: centre_of_mass,
+        },
+        &mut skater.player_input.processed,
+        &mut owners,
+        &skater.animation.packet.hierarchy,
+        &collision,
+        physics.settings.step.simulation,
+        |update| {
+            physics.riding.update_biped_reckoning(
+                &mut skater.air_reckoning.state,
+                update,
+                flags,
+                spin,
+            );
+            Ok(())
+        },
+    )?;
+    Ok(())
+}
 impl SkeletonInputRuntime {
     pub(crate) fn update_biped_ground<F>(
         &mut self,
diff --git a/crates/skate-game/src/physics/player_state/publication.rs b/crates/skate-game/src/physics/player_state/publication.rs
index 4bbbc9d0..8a20fdc9 100644
--- a/crates/skate-game/src/physics/player_state/publication.rs
+++ b/crates/skate-game/src/physics/player_state/publication.rs
@@ -124,14 +124,6 @@ pub(super) fn publish(physics: &mut GamePhysics, skater: &mut SkaterRuntime) ->
         //State Fill82D3B010 is a single byte from this retained Slide owner.
         physical.state.signed_ground_step_84 = u8::from(skater.slide_state.state.wall_riding);
     }
-    //ProcessOutput82DB71C4 calls SkateboardController::FillPhysOut82D76D20
-    //for every selected state. The constructor82D74DD8 seeds448=0; use the
-    //same controller owner as state transitions and post-physics ragdoll.
-    physical.off_board.dropping_board_322 = u8::from(p.flags_2476 & (1 << 9) != 0);
-    physical.off_board.retrieving_board_323 = u8::from(
-        p.flags_2476 & (1 << 10) != 0 || skater.skateboard_controller.fields.state_448 == 4,
-    );
-
     //ProcessOutput82DB7130..7180 copies the HandPlantManager animation
     //flags1876 into Air304+20 one bit at a time, preserving the low28 bits.
     //The same manager word is consumed by the actual input publication.
@@ -177,5 +169,6 @@ pub(super) fn publish(physics: &mut GamePhysics, skater: &mut SkaterRuntime) ->
     if state == PhysicalStateId::Teleporting {
         skater.teleport_state.publish_output(&mut skater.player_input.physical);
     }
+    super::super::offboard::possession::publish(physics, skater)?;
     Ok(())
 }
diff --git a/crates/skate-game/src/physics/player_state/transition.rs b/crates/skate-game/src/physics/player_state/transition.rs
index d4155d41..e90afb6a 100644
--- a/crates/skate-game/src/physics/player_state/transition.rs
+++ b/crates/skate-game/src/physics/player_state/transition.rs
@@ -35,15 +35,6 @@ impl PhysicalStateCalls for Calls {
         ));
     }
 }
-struct InactiveController;
-impl SkateboardControllerActions for InactiveController {
-    fn hold_skateboard(&mut self) {
-        unreachable!("active controller rejected before transition")
-    }
-    fn let_go_of_skateboard(&mut self) {
-        unreachable!("active controller rejected before transition")
-    }
-}
 pub(super) fn set(
     physics: &mut GamePhysics,
     skater: &mut SkaterRuntime,
@@ -81,11 +72,29 @@ pub(super) fn set(
             "Physical state transition {current:?} -> {requested:?} requires its native Enter/Exit production adapter"
         ));
     }
-    if skater.skateboard_controller.fields.system_on_452 {
-        return Err(
-            "Ground transition requires active SkateboardController::LetGoOfSkateboard".into(),
-        );
+    if skater.player_input.toolkit.is_none() {
+        skater.player_input.toolkit = Some(BoardToolkit::from_board(
+            &physics.board,
+            skater.player_input.processed.flags_2468,
+            skater.player_input.processed.scalar_2612,
+            skater.player_input.processed.vectors_464_480_496_512_528[0].map(f32::from_bits),
+            [0.0, 1.0, 0.0, 0.0],
+        ));
     }
+    let observation = super::super::offboard::possession::observe(physics, skater)?;
+    let offboard = &mut skater.offboard;
+    let mut controller_actions = super::super::offboard::possession::Actions {
+        state: &mut offboard.possession,
+        settings: &offboard.possession_settings,
+        observation: &observation,
+        effects: super::super::offboard::board_effects::BoardEffects {
+            board: &mut physics.board,
+            animated: &mut skater.ground_lifecycle.board_animated_290,
+            policy: &mut offboard.board_policy,
+            standard_deck_drag: offboard.standard_deck_drag,
+            timestep: skater.player_input.processed.timestep_2604,
+        },
+    };
     let p = &mut skater.player_input.processed;
     let player = &mut skater.player_input.player;
     let mut data = StateChangeData {
@@ -114,7 +123,7 @@ pub(super) fn set(
             requested as u32,
             &mut data,
             &mut Calls,
-            &mut InactiveController,
+            &mut controller_actions,
         )
         .map_err(|e| format!("Unknown physical state {}", e.0))?;
     player.state_count_1312 = data.player.word_1312;
@@ -129,15 +138,6 @@ pub(super) fn set(
     p.state_count_2564 = data.processed.word_2564;
     p.state_timer_2664 = data.processed.scalar_2664;
     skater.skateboard_controller.fields = data.skateboard_controller;
-    if skater.player_input.toolkit.is_none() {
-        skater.player_input.toolkit = Some(BoardToolkit::from_board(
-            &physics.board,
-            p.flags_2468,
-            p.scalar_2612,
-            p.vectors_464_480_496_512_528[0].map(f32::from_bits),
-            [0.0, 1.0, 0.0, 0.0],
-        ));
-    }
     //Native82DB8540 publishes Processed state/history BEFORE old Exit. The
     //same retained objects then receive Exit followed by the new Enter.
     match current {
@@ -159,7 +159,10 @@ pub(super) fn set(
         PhysicalStateId::GroundAnimation => super::super::ground_animation::enter(physics, skater),
         PhysicalStateId::SlideGround => super::super::slide_state::enter(physics, skater),
         PhysicalStateId::WipeoutGround => super::super::wipeout_states::enter(physics, skater),
-        PhysicalStateId::Teleporting => { skater.teleport_state.enter(); Ok(()) },
+        PhysicalStateId::Teleporting => {
+            skater.teleport_state.enter();
+            Ok(())
+        }
         _ => unreachable!("state support checked before publication"),
     }
 }
diff --git a/crates/skate-game/src/physics/riding_outputs.rs b/crates/skate-game/src/physics/riding_outputs.rs
index dc3dfa60..30eded60 100644
--- a/crates/skate-game/src/physics/riding_outputs.rs
+++ b/crates/skate-game/src/physics/riding_outputs.rs
@@ -52,6 +52,30 @@ pub(crate) struct RidingOutputs {
     pending_wheel_queries: Option<[Option<WheelLineHit>; 4]>,
 }
 impl RidingOutputs {
+    ///Skeleton82BDE060's final82D8E3E0 call, argument7=true.
+    pub(crate) fn update_biped_reckoning(
+        &mut self,
+        air: &mut skate_core::air::reckoning::AirState,
+        input: super::offboard::skeleton_ground::ReckoningUpdate,
+        flags_2468: u32,
+        body_spin: f32,
+    ) {
+        let previous_up = lanes(self.reckoning.up);
+        skate_core::player::offboard::ground_reckoning::update(
+            &mut self.reckoning, &mut self.reckoning_frames, &mut self.body_spin, air,
+            skate_core::player::offboard::ground_reckoning::Settings {
+                ground_normal_smoothing: self.orientation_settings.ground_normal_smoothing,
+                tilt_vs_rotation: &self.tilt_vs_rotation,
+                tilt_vs_slope: &self.tilt_vs_slope,
+            },
+            skate_core::player::offboard::ground_reckoning::Input {
+                previous_up,
+                requested_up: input.up, requested_forward: input.forward, blend: input.blend,
+                reverse_stance: flags_2468 & 0x0010_0000 != 0,
+                enable_body_spin_input: true, physical_body_spin_2812: body_spin,
+            },
+        );
+    }
     ///Board82C0D680 resets CollisionInfo and both probes, preserving7692.
     pub fn reset_for_teleport(&mut self) {
         let elapsed = self.ground.time_without_wheel_contact;
diff --git a/crates/skate-game/src/physics/solve.rs b/crates/skate-game/src/physics/solve.rs
index cbe86f04..a6932a02 100644
--- a/crates/skate-game/src/physics/solve.rs
+++ b/crates/skate-game/src/physics/solve.rs
@@ -14,7 +14,11 @@ pub(super) fn advance(
     skater: &mut SkaterRuntime,
     truck_targets: [f32; 2],
 ) -> Result<(), String> {
-    let board_volumes = colliders::world_volumes(&physics.board, &physics.settings);
+    let board_volumes = if skater.offboard.board_policy.volumes_enabled {
+        colliders::world_volumes(&physics.board, &physics.settings)
+    } else {
+        Vec::new()
+    };
     let skeleton_volumes =
         skeleton_colliders::world_volumes(&skater.skeleton, &skater.skeleton_collision)?;
     // Each native assembly has its own query record and retention buffer.
@@ -55,6 +59,16 @@ pub(super) fn advance(
         ATTACHED_REACTION_BASE + PART_COUNT,
         dt,
     );
+    let skeleton_drive_count = drives.rows.len();
+    if skater.skateboard_controller.fields.system_on_452 {
+        super::offboard::hand_drives::append(
+            &mut drives.rows,
+            &skater.offboard.possession,
+            physics.board.bodies(),
+            skater.skeleton.bodies(),
+            dt,
+        );
+    }
     let bodies = skater
         .skeleton
         .bodies_mut()
@@ -77,6 +91,9 @@ pub(super) fn advance(
         .publish_physical_record(deck_frame(&physics.board));
     // These solved rows are consumed by the actual collision/drive feedback
     // phase; keep their identity and impulses after the shared solve.
+    //Controller drive descriptors have flags28=0: they are not Skeleton's
+    //spy drives and must not be paired with SkeletonDriveIdentity feedback.
+    drives.rows.truncate(skeleton_drive_count);
     skater.solved_drives = Some(drives);
     Ok(())
 }
diff --git a/docs/RUNOUT.md b/docs/RUNOUT.md
index c05b4dda..9167e33c 100644
--- a/docs/RUNOUT.md
+++ b/docs/RUNOUT.md
@@ -109,3 +109,40 @@ stock controller's real-floor test runs60 updates each for idle, half input and
 full input. This is controller/query coverage; production transitions still
 reject BipedGround until its complete physical adapter is available. No playable
 binary has been staged or launched from these changes.
+
+## Board possession and shared solver integration
+
+Native hand drives82D74FD8/82D751D8 now append to the existing board/skeleton
+island. Factory82AE64F8 stores its fifth argument as body A and fourth as B:
+hands3/7 therefore react against deck6. The skeleton's drive-spy results retain
+their original row count. Tests verify opposite hand/deck reactions and zero
+reaction after releasing the hand drive.
+
+The controller now has production hold/release, update and output adapters over
+the actual animated hand frames, physical hand contacts, board toolkit and
+retained collision normals. Its standard/released drag, hook drive and collision
+volume policies feed the existing physical owners. Native82C08818's surface vote
+is the producer of the controller's observed board840; it is not a sleeping flag.
+The lifecycle callback accepts the live controller fields so LetGo can preserve
+its eight-update throw countdown across a state change. Board positioning uses
+82C0B2C8 without clearing rates or pending forces, verified by regression test.
+
+Observed code comes from the generated TU3 functions and raw image
+default_82000000_011B0000.bin, SHA256
+f4aa113eb541bfba03dbc108cf5ab43f58c965b20fa3b82f9c40938a0ad841c4.
+Lookup8 proves893DA1B966231D76 is MaxDistance (hide trigger) and
+6CFF6F2C43F0AD41 is DistanceToHideSkateboard (hidden position offset), correcting
+the earlier reversed inference. The biped skeleton adapter also borrows the live roots,
+IK, collision and shared reckoning owners, including native body-spin input.
+
+The thrown-board update750F0 calls82C07328 three times. These outputs are angular
+displacements:07328 removes the current per-step motion along the requested axis
+and uses inverse-tensor/step/tensor conversion to add angular acceleration. It
+does not apply the outputs as raw torque. A regression covers braking overshoot
+and correcting opposite motion while preserving perpendicular angular velocity.
+
+Validation:459 core tests and83 game tests passed, including the final
+output/skeleton-owner wiring, private map and stock difficulty tests. These
+are still component and existing-state tests: BipedGround/BipedAir state
+integration and remount remain unfinished. The runout crash is not yet fixed
+in a staged playable build.