diff --git a/source/isaaclab/changelog.d/henry-go2-base-height-inf-guard.rst b/source/isaaclab/changelog.d/henry-go2-base-height-inf-guard.rst
new file mode 100644
index 000000000000..a64094f7ef1f
--- /dev/null
+++ b/source/isaaclab/changelog.d/henry-go2-base-height-inf-guard.rst
@@ -0,0 +1,7 @@
+Fixed
+^^^^^
+
+* Fixed :func:`~isaaclab.envs.mdp.rewards.base_height_l2` returning an infinite reward for any
+  environment whose own height scan contained a missed ray, since ``ray_hits_w`` reports ``inf``
+  for a ray that finds nothing within its ``max_distance`` rather than a clamped value. Now only
+  finite ray hits are averaged into the terrain-adjusted target height.
diff --git a/source/isaaclab/isaaclab/envs/mdp/rewards.py b/source/isaaclab/isaaclab/envs/mdp/rewards.py
index 0c96e700f76d..127c8cd3d9b4 100644
--- a/source/isaaclab/isaaclab/envs/mdp/rewards.py
+++ b/source/isaaclab/isaaclab/envs/mdp/rewards.py
@@ -131,12 +131,22 @@ def base_height_l2(
     Note:
         For flat terrain, target height is in the world frame. For rough terrain,
         sensor readings can adjust the target height to account for the terrain.
+
+    Note:
+        A ray that hits nothing within its ``max_distance`` reports ``inf`` rather than a clamped
+        value, so only finite hits are averaged into the terrain-adjusted target height. An
+        environment whose rays all miss falls back to the unadjusted ``target_height``.
     """
     asset: RigidObject = env.scene[asset_cfg.name]
     if sensor_cfg is not None:
         sensor: RayCaster = env.scene[sensor_cfg.name]
-        # Adjust the target height using the sensor data
-        adjusted_target_height = target_height + torch.mean(sensor.data.ray_hits_w.torch[..., 2], dim=1)
+        # Adjust the target height using the sensor data, ignoring rays that missed the terrain
+        ray_hits_z = sensor.data.ray_hits_w.torch[..., 2]
+        finite_hits = torch.isfinite(ray_hits_z)
+        safe_hits = torch.where(finite_hits, ray_hits_z, torch.zeros_like(ray_hits_z))
+        hit_count = finite_hits.sum(dim=1).clamp(min=1)
+        terrain_height = safe_hits.sum(dim=1) / hit_count
+        adjusted_target_height = target_height + terrain_height
     else:
         # Use the provided target height directly for flat terrain
         adjusted_target_height = target_height
diff --git a/source/isaaclab_experimental/changelog.d/warp-base-height-reward.rst b/source/isaaclab_experimental/changelog.d/warp-base-height-reward.rst
new file mode 100644
index 000000000000..e90c5e8cc9ef
--- /dev/null
+++ b/source/isaaclab_experimental/changelog.d/warp-base-height-reward.rst
@@ -0,0 +1,5 @@
+Fixed
+^^^^^
+
+* Added the Warp implementation of ``base_height_l2``, restoring Warp frontend support for
+  Unitree Go2 tasks with the base-height reward enabled.
diff --git a/source/isaaclab_experimental/isaaclab_experimental/envs/mdp/rewards.py b/source/isaaclab_experimental/isaaclab_experimental/envs/mdp/rewards.py
index bcebee08725a..880697b562f2 100644
--- a/source/isaaclab_experimental/isaaclab_experimental/envs/mdp/rewards.py
+++ b/source/isaaclab_experimental/isaaclab_experimental/envs/mdp/rewards.py
@@ -206,6 +206,43 @@ def flat_orientation_l2(env: ManagerBasedRLEnv, out, asset_cfg: SceneEntityCfg =
     )
 
 
+@wp.kernel
+def _base_height_l2_kernel(
+    root_pose_w: wp.array(dtype=wp.transformf),
+    ray_hits_w: wp.array(dtype=wp.vec3f, ndim=2),
+    target_height: float,
+    out: wp.array(dtype=wp.float32),
+):
+    i = wp.tid()
+    height_sum = float(0.0)
+    hit_count = int(0)
+    if ray_hits_w:
+        for ray in range(ray_hits_w.shape[1]):
+            height = ray_hits_w[i, ray][2]
+            if wp.isfinite(height):
+                height_sum += height
+                hit_count += 1
+    error = wp.transform_get_translation(root_pose_w[i])[2] - target_height - height_sum / float(wp.max(hit_count, 1))
+    out[i] = error * error
+
+
+def base_height_l2(
+    env: ManagerBasedRLEnv,
+    out: wp.array(dtype=wp.float32),
+    target_height: float,
+    asset_cfg: SceneEntityCfg = SceneEntityCfg("robot"),
+    sensor_cfg: SceneEntityCfg | None = None,
+) -> None:
+    """Penalize squared base-height error from ``target_height`` [m], relative to finite terrain hits."""
+    ray_hits = env.scene[sensor_cfg.name].data.ray_hits_w if sensor_cfg is not None else None
+    wp.launch(
+        _base_height_l2_kernel,
+        dim=env.num_envs,
+        inputs=[env.scene[asset_cfg.name].data.root_link_pose_w, ray_hits, target_height, out],
+        device=env.device,
+    )
+
+
 """
 Joint penalties.
 """
diff --git a/source/isaaclab_experimental/test/envs/mdp/test_capture_safety.py b/source/isaaclab_experimental/test/envs/mdp/test_capture_safety.py
index 7fbc95efebe7..ea69b3308fc4 100644
--- a/source/isaaclab_experimental/test/envs/mdp/test_capture_safety.py
+++ b/source/isaaclab_experimental/test/envs/mdp/test_capture_safety.py
@@ -30,6 +30,7 @@
 import inspect
 import pkgutil
 from collections.abc import Callable
+from functools import partial
 from types import SimpleNamespace
 
 import numpy as np
@@ -44,25 +45,32 @@
 import isaaclab_experimental.envs.mdp.terminations as warp_term
 import isaaclab_tasks_experimental.core as tasks_experimental_core
 import isaaclab_tasks_experimental.core.locomotion.mdp.rewards as warp_loco_rew
+import isaaclab_tasks_experimental.core.velocity.mdp.rewards as warp_velocity_rew
 from parity_helpers import (
     DEVICE,
     NUM_BODIES,
     NUM_ENVS,
     MockArticulation,
     MockArticulationData,
+    MockCommandManager,
     MockPoseCommandManager,
     MockScene,
+    MockSensorCfg,
     MockTerminationManager,
     assert_close,
     assert_equal,
+    copy_np_to_wp,
     make_pose_command_term,
     mutate_body_data,
+    proxy_array,
 )
 
 import isaaclab.envs.mdp.rewards as stable_rew
 import isaaclab.envs.mdp.terminations as stable_term
 from isaaclab.managers.manager_term_cfg import RewardTermCfg, TerminationTermCfg
 
+import isaaclab_tasks.core.velocity.mdp.rewards as stable_velocity_rew
+
 
 @dataclasses.dataclass(frozen=True)
 class CaptureCase:
@@ -236,6 +244,53 @@ def mutate() -> None:
     )
 
 
+def _build_base_height_l2(terrain: bool) -> CaptureCase:
+    art_data = MockArticulationData(num_bodies=NUM_BODIES)
+    hits = np.random.default_rng(17).normal(size=(NUM_ENVS, 4, 3)).astype(np.float32)
+    hits[::2, 0, 2] = np.inf
+    hits[::3, 1, 2] = -np.inf
+    hits[::5, :, 2] = np.nan  # No finite hits: use the flat-ground target.
+    ray_hits = proxy_array(hits, dtype=wp.vec3f, device=DEVICE)
+    scene = {
+        "robot": MockArticulation(art_data),
+        "height_scanner": SimpleNamespace(data=SimpleNamespace(ray_hits_w=ray_hits)),
+    }
+    env = SimpleNamespace(scene=scene, num_envs=NUM_ENVS, device=DEVICE)
+    params = dict(target_height=0.35, sensor_cfg=MockSensorCfg("height_scanner") if terrain else None)
+
+    def mutate():
+        mutate_body_data(art_data)
+        copy_np_to_wp(ray_hits, hits + 0.3)
+
+    return CaptureCase(warp_rew.base_height_l2, stable_rew.base_height_l2, env, env, params, mutate)
+
+
+def _build_feet_air_time_variance(body_ids=(0, 2)) -> CaptureCase:
+    rng = np.random.default_rng(23)
+    air = rng.uniform(0.0, 1.0, (NUM_ENVS, NUM_BODIES)).astype(np.float32)
+    contact = rng.uniform(0.0, 1.0, air.shape).astype(np.float32)
+    data = SimpleNamespace(
+        last_air_time=proxy_array(air, device=DEVICE), last_contact_time=proxy_array(contact, device=DEVICE)
+    )
+    scene = SimpleNamespace(sensors={"contact_sensor": SimpleNamespace(data=data)})
+    command = torch.tensor(rng.normal(size=(NUM_ENVS, 3)), dtype=torch.float32, device=DEVICE)
+    command[::2, :2] = 0.0  # Yaw-only commands must not incur this penalty.
+    command[1, :2] = torch.tensor([0.06, 0.07], device=DEVICE)
+    env = SimpleNamespace(
+        scene=scene, command_manager=MockCommandManager(command, None), num_envs=NUM_ENVS, device=DEVICE
+    )
+    params = dict(command_name="vel", sensor_cfg=MockSensorCfg(body_ids=list(body_ids)), max_time=0.5)
+
+    def mutate():
+        copy_np_to_wp(data.last_air_time, 1.0 - air)
+        copy_np_to_wp(data.last_contact_time, 1.0 - contact)
+        command.copy_(command.roll(1, dims=0))
+
+    return CaptureCase(
+        warp_velocity_rew.feet_air_time_variance, stable_velocity_rew.feet_air_time_variance, env, env, params, mutate
+    )
+
+
 _SHARED_REW = "isaaclab_experimental.envs.mdp.rewards"
 _SHARED_TERM = "isaaclab_experimental.envs.mdp.terminations"
 _LOCO_REW = "isaaclab_tasks_experimental.core.locomotion.mdp.rewards"
@@ -245,6 +300,14 @@ def mutate() -> None:
     CaptureSpec(_SHARED_TERM, "pose_command_success", "termination", _build_pose_command_success),
     CaptureSpec(_LOCO_REW, "terminated_penalty", "reward", _build_terminated_penalty),
     CaptureSpec(_LOCO_REW, "survival_success_rate", "reward", _build_survival_success_rate, expect_nonzero=False),
+    CaptureSpec(_SHARED_REW, "base_height_l2", "reward", partial(_build_base_height_l2, terrain=False)),
+    CaptureSpec(_SHARED_REW, "base_height_l2", "reward", partial(_build_base_height_l2, terrain=True)),
+    CaptureSpec(
+        "isaaclab_tasks_experimental.core.velocity.mdp.rewards",
+        "feet_air_time_variance",
+        "reward",
+        _build_feet_air_time_variance,
+    ),
 ]
 
 
@@ -458,6 +521,14 @@ def test_term_is_capture_safe(spec: CaptureSpec):
         assert expected.any(), "mutated inputs produced a degenerate expectation; the replay proves little"
 
 
+def test_feet_air_time_variance_requires_two_feet():
+    case = _build_feet_air_time_variance(body_ids=[0])
+    with pytest.raises(RuntimeError, match="at least two bodies"):
+        case.stable_fn(case.stable_env, **case.params)
+    with pytest.raises(RuntimeError, match="at least two bodies"):
+        case.warp_fn(case.warp_env, wp.empty(NUM_ENVS, dtype=wp.float32, device=DEVICE), **case.params)
+
+
 def test_survival_success_rate_reset_is_capture_safe():
     """The metric is produced by ``reset()``, not ``__call__``, so capture it separately.
 
diff --git a/source/isaaclab_tasks/changelog.d/henry-cassie-gait-symmetry.minor.rst b/source/isaaclab_tasks/changelog.d/henry-cassie-gait-symmetry.minor.rst
new file mode 100644
index 000000000000..0da0e419b2b7
--- /dev/null
+++ b/source/isaaclab_tasks/changelog.d/henry-cassie-gait-symmetry.minor.rst
@@ -0,0 +1,13 @@
+Added
+^^^^^
+
+* Added :func:`~isaaclab_tasks.core.velocity.mdp.rewards.feet_air_time_variance`, penalizing an
+  uneven swing/stance split between a biped's feet.
+
+Changed
+^^^^^^^
+
+* Changed ``Isaac-Velocity-Flat-Cassie``, ``Isaac-Velocity-Rough-Cassie`` and
+  ``Isaac-Velocity-Flat-H1`` to include the new ``air_time_variance`` reward term, which fixes the
+  tilted gait these tasks otherwise converge on. Policies trained on them will differ from ones
+  trained before this change; set the weight to ``0.0`` to recover the previous reward.
diff --git a/source/isaaclab_tasks/changelog.d/henry-go2-crouch-and-gait-fix.minor.rst b/source/isaaclab_tasks/changelog.d/henry-go2-crouch-and-gait-fix.minor.rst
new file mode 100644
index 000000000000..022ede555879
--- /dev/null
+++ b/source/isaaclab_tasks/changelog.d/henry-go2-crouch-and-gait-fix.minor.rst
@@ -0,0 +1,12 @@
+Changed
+^^^^^^^
+
+* Changed ``Isaac-Velocity-Flat-UnitreeGo2`` and ``Isaac-Velocity-Rough-UnitreeGo2`` to add a
+  ``base_height_l2`` reward term at weight ``-30.0`` (rough, height-scanner adjusted) and disabled
+  on flat via ``sensor_cfg=None``. Without it, Go2's leg colliders let a policy rest its weight on
+  the legs and collect the full episode-length alive bonus from a permanent crouch, since torso
+  contact never fires and flat-orientation reward can't see it.
+* Changed ``action_rate_l2`` on both tasks from the shared default of ``-0.01`` to ``-0.005``. The
+  stronger penalty locked one hind foot into a low-amplitude, dragging gait on flat terrain with
+  the Newton backend. Policies trained on these tasks will differ from ones trained before this
+  change.
diff --git a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/cassie/flat_env_cfg.py b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/cassie/flat_env_cfg.py
index 73804d550de0..9112a0757808 100644
--- a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/cassie/flat_env_cfg.py
+++ b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/cassie/flat_env_cfg.py
@@ -31,6 +31,7 @@ def __post_init__(self):
         # rewards
         self.rewards.flat_orientation_l2.weight = -2.5
         self.rewards.feet_air_time.weight = 5.0
+        self.rewards.air_time_variance.weight = -10.0
         self.rewards.joint_deviation_hip.params["asset_cfg"].joint_names = ["hip_rotation_.*"]
         # curriculum
         self.curriculum.terrain_levels = None
diff --git a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/cassie/rough_env_cfg.py b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/cassie/rough_env_cfg.py
index 84f38bed9ffe..1c4b565934bb 100644
--- a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/cassie/rough_env_cfg.py
+++ b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/cassie/rough_env_cfg.py
@@ -42,6 +42,15 @@ class CassieRewardsCfg(RewardsCfg):
         weight=-0.2,
         params={"asset_cfg": SceneEntityCfg("robot", joint_names=["toe_joint_.*"])},
     )
+    # fixes the tilted gait
+    air_time_variance = RewTerm(
+        func=mdp.feet_air_time_variance,
+        weight=-5.0,
+        params={
+            "sensor_cfg": SceneEntityCfg("contact_forces", body_names=".*toe"),
+            "command_name": "base_velocity",
+        },
+    )
     # penalize toe joint limits
     dof_pos_limits = RewTerm(
         func=mdp.joint_pos_limits,
diff --git a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/go2/flat_env_cfg.py b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/go2/flat_env_cfg.py
index 46f3f9effadc..4237f735d0d0 100644
--- a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/go2/flat_env_cfg.py
+++ b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/go2/flat_env_cfg.py
@@ -31,5 +31,6 @@ def __post_init__(self):
         # rewards
         self.rewards.flat_orientation_l2.weight = -2.5
         self.rewards.feet_air_time.weight = 0.25
+        self.rewards.base_height_l2.params["sensor_cfg"] = None
         # curriculum
         self.curriculum.terrain_levels = None
diff --git a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/go2/rough_env_cfg.py b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/go2/rough_env_cfg.py
index bcd1c051417c..71160e332795 100644
--- a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/go2/rough_env_cfg.py
+++ b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/go2/rough_env_cfg.py
@@ -5,17 +5,42 @@
 
 """Configuration for the Unitree Go2 velocity-tracking environment on rough terrain."""
 
+from isaaclab.managers import RewardTermCfg as RewTerm
+from isaaclab.managers import SceneEntityCfg
 from isaaclab.utils import configclass, replace
 
 from isaaclab_assets.robots.unitree import UNITREE_GO2_CFG
 
-from ...velocity_env_cfg import LocomotionVelocityRoughEnvCfg
+from ... import mdp
+from ...velocity_env_cfg import LocomotionVelocityRoughEnvCfg, RewardsCfg
+
+# UNITREE_GO2_CFG.init_state.pos is (0, 0, 0.4) -- the asset's own authored standing height.
+_GO2_STANDING_HEIGHT = 0.4
+
+
+@configclass
+class UnitreeGo2Rewards(RewardsCfg):
+    """Adds a base-height term on top of the shared velocity rewards.
+
+    The stock velocity task has no term constraining base height. Go2 carries colliders on its
+    legs (not just the feet), so a policy can rest its weight on the legs and collect the full
+    episode-length alive bonus from a permanent crouch -- torso-contact termination never fires
+    and flat-orientation reward can't see it, since the torso stays level while the robot sinks.
+    """
+
+    base_height_l2 = RewTerm(
+        func=mdp.base_height_l2,
+        weight=0.0,
+        params={"target_height": _GO2_STANDING_HEIGHT},
+    )
 
 
 @configclass
 class UnitreeGo2RoughEnvCfg(LocomotionVelocityRoughEnvCfg):
     """Configuration for the Unitree Go2 velocity-tracking environment on rough terrain."""
 
+    rewards: UnitreeGo2Rewards = UnitreeGo2Rewards()
+
     def __post_init__(self):
         super().__post_init__()
 
@@ -42,5 +67,11 @@ def __post_init__(self):
         self.rewards.track_lin_vel_xy_exp.weight = 1.5
         self.rewards.track_ang_vel_z_exp.weight = 0.75
         self.rewards.dof_acc_l2.weight = -2.5e-7
+        # base_height_l2: rough terrain, adjust target height using the height-scanner rays.
+        self.rewards.base_height_l2.weight = -30.0
+        self.rewards.base_height_l2.params["sensor_cfg"] = SceneEntityCfg("height_scanner")
+        # action_rate_l2: halved from the shared default of -0.01. The stronger penalty locked
+        # one hind foot into a low-amplitude, dragging gait on flat terrain with Newton.
+        self.rewards.action_rate_l2.weight = -0.005
         # terminations
         self.terminations.base_contact.params["sensor_cfg"].body_names = "base"
diff --git a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/h1/flat_env_cfg.py b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/h1/flat_env_cfg.py
index 1db600e46532..2d98123dff34 100644
--- a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/h1/flat_env_cfg.py
+++ b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/config/h1/flat_env_cfg.py
@@ -5,15 +5,36 @@
 
 """Configuration for the Unitree H1 velocity-tracking environment on flat terrain."""
 
+from isaaclab.managers import RewardTermCfg as RewTerm
+from isaaclab.managers import SceneEntityCfg
 from isaaclab.utils import configclass
 
-from .rough_env_cfg import H1RoughEnvCfg
+import isaaclab_tasks.core.velocity.mdp as mdp
+
+from .rough_env_cfg import H1Rewards, H1RoughEnvCfg
+
+
+@configclass
+class H1FlatRewards(H1Rewards):
+    """Reward terms for the MDP."""
+
+    # fixes the tilted gait
+    air_time_variance = RewTerm(
+        func=mdp.feet_air_time_variance,
+        weight=-2.0,
+        params={
+            "sensor_cfg": SceneEntityCfg("contact_forces", body_names=".*ankle_link"),
+            "command_name": "base_velocity",
+        },
+    )
 
 
 @configclass
 class H1FlatEnvCfg(H1RoughEnvCfg):
     """Configuration for the Unitree H1 velocity-tracking environment on flat terrain."""
 
+    rewards: H1FlatRewards = H1FlatRewards()
+
     def __post_init__(self):
         super().__post_init__()
 
diff --git a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/mdp/__init__.pyi b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/mdp/__init__.pyi
index 025fecca866a..88a90656769f 100644
--- a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/mdp/__init__.pyi
+++ b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/mdp/__init__.pyi
@@ -6,6 +6,7 @@
 __all__ = [
     "feet_air_time",
     "feet_air_time_positive_biped",
+    "feet_air_time_variance",
     "feet_slide",
     "stand_still_joint_deviation_l1",
     "terrain_levels_vel",
@@ -18,6 +19,7 @@ from .curriculums import terrain_levels_vel
 from .rewards import (
     feet_air_time,
     feet_air_time_positive_biped,
+    feet_air_time_variance,
     feet_slide,
     stand_still_joint_deviation_l1,
     track_ang_vel_z_world_exp,
diff --git a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/mdp/rewards.py b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/mdp/rewards.py
index 45a9a6b42125..83efe1ebe697 100644
--- a/source/isaaclab_tasks/isaaclab_tasks/core/velocity/mdp/rewards.py
+++ b/source/isaaclab_tasks/isaaclab_tasks/core/velocity/mdp/rewards.py
@@ -67,6 +67,39 @@ def feet_air_time_positive_biped(
     return reward
 
 
+def feet_air_time_variance(
+    env: ManagerBasedRLEnv, command_name: str, sensor_cfg: SceneEntityCfg, max_time: float = 0.5
+) -> torch.Tensor:
+    """Penalize an uneven swing/stance split between the feet.
+
+    The penalty is the variance across feet of the last completed swing and stance durations [s],
+    each clipped at ``max_time`` [s], and is zero for near-zero commands.
+
+    Raises:
+        RuntimeError: If ``sensor_cfg`` resolves to fewer than two bodies, where :func:`torch.var`
+            would return ``nan``.
+    """
+    # extract the used quantities (to enable type-hinting)
+    contact_sensor: ContactSensor = env.scene.sensors[sensor_cfg.name]
+    # compute the penalty
+    last_air_time = contact_sensor.data.last_air_time.torch[:, sensor_cfg.body_ids]
+    last_contact_time = contact_sensor.data.last_contact_time.torch[:, sensor_cfg.body_ids]
+    # ``body_ids`` may be a slice, so count the bodies the selection actually resolved to
+    num_feet = last_air_time.shape[1]
+    if num_feet < 2:
+        raise RuntimeError(
+            f"'feet_air_time_variance' needs at least two bodies to take a variance across feet, but"
+            f" '{sensor_cfg.name}' resolved to {num_feet}. Widen 'body_names' on its 'sensor_cfg' to"
+            " cover every foot."
+        )
+    penalty = torch.var(torch.clip(last_air_time, max=max_time), dim=1) + torch.var(
+        torch.clip(last_contact_time, max=max_time), dim=1
+    )
+    # no penalty for zero command
+    penalty *= torch.linalg.norm(env.command_manager.get_command(command_name)[:, :2], dim=1) > 0.1
+    return penalty
+
+
 def feet_slide(
     env: ManagerBasedRLEnv, sensor_cfg: SceneEntityCfg, asset_cfg: SceneEntityCfg = SceneEntityCfg("robot")
 ) -> torch.Tensor:
diff --git a/source/isaaclab_tasks_experimental/changelog.d/warp-air-time-variance-reward.rst b/source/isaaclab_tasks_experimental/changelog.d/warp-air-time-variance-reward.rst
new file mode 100644
index 000000000000..646b97634a7a
--- /dev/null
+++ b/source/isaaclab_tasks_experimental/changelog.d/warp-air-time-variance-reward.rst
@@ -0,0 +1,5 @@
+Fixed
+^^^^^
+
+* Added the Warp implementation of ``feet_air_time_variance``, restoring Warp frontend support
+  for Cassie and H1 tasks with the gait-symmetry reward enabled.
diff --git a/source/isaaclab_tasks_experimental/isaaclab_tasks_experimental/core/velocity/mdp/__init__.pyi b/source/isaaclab_tasks_experimental/isaaclab_tasks_experimental/core/velocity/mdp/__init__.pyi
index ae4b6d7af547..c9a51b09123b 100644
--- a/source/isaaclab_tasks_experimental/isaaclab_tasks_experimental/core/velocity/mdp/__init__.pyi
+++ b/source/isaaclab_tasks_experimental/isaaclab_tasks_experimental/core/velocity/mdp/__init__.pyi
@@ -7,6 +7,7 @@ __all__ = [
     "terrain_levels_vel",
     "feet_air_time",
     "feet_air_time_positive_biped",
+    "feet_air_time_variance",
     "feet_slide",
     "stand_still_joint_deviation_l1",
     "track_ang_vel_z_world_exp",
@@ -22,6 +23,7 @@ from .curriculums import terrain_levels_vel
 from .rewards import (
     feet_air_time,
     feet_air_time_positive_biped,
+    feet_air_time_variance,
     feet_slide,
     stand_still_joint_deviation_l1,
     track_ang_vel_z_world_exp,
diff --git a/source/isaaclab_tasks_experimental/isaaclab_tasks_experimental/core/velocity/mdp/rewards.py b/source/isaaclab_tasks_experimental/isaaclab_tasks_experimental/core/velocity/mdp/rewards.py
index 345e8844b7fc..4861b58e5e33 100644
--- a/source/isaaclab_tasks_experimental/isaaclab_tasks_experimental/core/velocity/mdp/rewards.py
+++ b/source/isaaclab_tasks_experimental/isaaclab_tasks_experimental/core/velocity/mdp/rewards.py
@@ -138,6 +138,56 @@ def feet_air_time_positive_biped(env, out, command_name: str, threshold: float,
     )
 
 
+@wp.kernel
+def _feet_air_time_variance_kernel(
+    air_time: wp.array(dtype=wp.float32, ndim=2),
+    contact_time: wp.array(dtype=wp.float32, ndim=2),
+    body_ids: wp.array(dtype=wp.int32),
+    command: wp.array(dtype=wp.float32, ndim=2),
+    max_time: float,
+    out: wp.array(dtype=wp.float32),
+):
+    i = wp.tid()
+    mean = wp.vec2f()
+    for foot in range(body_ids.shape[0]):
+        body = body_ids[foot]
+        mean += wp.vec2f(wp.min(air_time[i, body], max_time), wp.min(contact_time[i, body], max_time))
+    mean /= float(body_ids.shape[0])
+    variance = float(0.0)
+    for foot in range(body_ids.shape[0]):
+        body = body_ids[foot]
+        times = wp.vec2f(wp.min(air_time[i, body], max_time), wp.min(contact_time[i, body], max_time))
+        variance += wp.length_sq(times - mean)
+    moving = wp.length(wp.vec2f(command[i, 0], command[i, 1])) > 0.1
+    out[i] = wp.where(moving, variance / float(body_ids.shape[0] - 1), 0.0)
+
+
+def feet_air_time_variance(
+    env: ManagerBasedRLEnv,
+    out: wp.array(dtype=wp.float32),
+    command_name: str,
+    sensor_cfg: SceneEntityCfg,
+    max_time: float = 0.5,
+) -> None:
+    """Penalize sample variance of foot air/contact durations, capped at ``max_time`` [s], while moving."""
+    if sensor_cfg.body_ids_wp.shape[0] < 2:
+        raise RuntimeError("'feet_air_time_variance' needs at least two bodies to take a variance across feet.")
+    data = env.scene.sensors[sensor_cfg.name].data
+    wp.launch(
+        _feet_air_time_variance_kernel,
+        dim=env.num_envs,
+        inputs=[
+            data.last_air_time,
+            data.last_contact_time,
+            sensor_cfg.body_ids_wp,
+            wp.from_torch(env.command_manager.get_command(command_name)),
+            max_time,
+            out,
+        ],
+        device=env.device,
+    )
+
+
 # ---------------------------------------------------------------------------
 # feet_slide
 # ---------------------------------------------------------------------------