What causes a character sinking into a descending moving platform?

The controller resolves grounding before the platform moves down, so by the time the platform has descended the character is left briefly overlapping it and snaps in and out each frame.

How do I catch this when it only happens for some players?

Capture it automatically from the player's device with the full stack trace, the device and OS, the build, and a breadcrumb trail of what they did. That turns a vague complaint into a specific, reproducible issue you can fix without owning the hardware it happens on.

How to Fix a Character Sinking Into the Floor on a Descending Platform

Quick answer: Move the platform first, then carry the rider and run the controller's collision resolve, so the character always sits on the platform's updated position.

On a descending platform a rider that visibly sinks each frame is an update-order problem. Move the platform before resolving the player. Here is how.

How to fix it

1. Move platforms before riders

Update all moving platforms first in the physics step, then apply the carry to riders and run the character controller's collision resolution against the platform's new position.

2. Carry by position delta

Apply the platform's per-frame downward delta to the rider so they descend with it, then let the ground check re-seat them exactly on the surface rather than overlapping it.

3. Use consistent fixed-step timing

Run both the platform and the controller in the same fixed-timestep callback so their motion advances together and the rider never lags a frame behind the platform.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.

Reproduce it once with full context and the fix writes itself. The hunt is the expensive part.