What causes tower defense pathfinding when towers block?

Placing a tower can fully block the only path, leaving enemies with no route, so they freeze, glitch, or the placement should have been disallowed but was not.

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 Tower Defense Pathfinding When Towers Block the Path

Quick answer: Recompute paths when towers change, disallow placements that fully block all enemies, and repath existing enemies to the new route.

Maze tower defense breaks when a tower blocks the path. Validating placement and repathing fixes it. Here is how.

How to fix it

1. Disallow fully-blocking placements

Before confirming a tower placement, check that a path still exists from every spawn to the goal. If the placement would seal off all routes, reject it so enemies always have a way through.

2. Recompute paths on tower changes

When a tower is placed or sold, the maze changes. Recompute the path so enemies follow the new route. Stale paths send enemies into walls or along routes that no longer exist.

3. Repath existing enemies

Enemies already on the map must repath to the updated route when the maze changes, not just newly spawned ones. Repath all active enemies so none freeze on a now-blocked path.

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.

Ship the fix, watch the signature disappear from the next build. That's how you know it's really gone.