Spider Spawners in the Trial Chambers spit out tons of spider mobs, but alot of them get stuck on walls and or climb up to the ceiling, still hostile but seem stuck, and it didn't seem to be a lighting thing either, they just ended up caught on the wall and barely try to get to me.
Its funny but as a challenge, its not really one if they all get stuck on the ceiling and forget about the player.
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We're tracking this issue in MC-151054 and MC-154160, so this ticket is being resolved and linked as a duplicate.
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