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The guy in front of the sarge dude is probably blocking the tile for the dudes death animation. Instead the game tries to do a workaround and have the dude fall either left or right. As I see it from the pic, this would mean falling into water with the upper half of the body, which requires a different kind of animation. I think this "could" be a problem. The exact same situation is certainly tough to recreate in a regular game.
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