Ancient Guardian can escape into the void

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I believe this is an extremely old oddity thats been in the game since the beginning, whereas an entity with large hitboxes and sufficient speed can "climb over" obstacles if they collide into it. It's difficult to describe, but is easy to replicate if you mod this into a player.

We made the gravestones no longer block movement, so there are still probably ways to have him bump over the wall.. but this common case should not happen so much now.

Changed Status to Fixed