When we kill mobs (some not all, but does not seem to be mob type specific) sometimes the mob doesn't disappear with the death animation, it just stays frozen in place, you aren't able to keep hitting it, it's kind of like a frozen ghost? it still makes noises but you can't interact or hit it, and it can't hit you. So far this has happened to an Enderman, a Zombie, and a Spider.
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Thank you for your report!
We're tracking this issue in MCPE-143194, so this ticket is being resolved and linked as a duplicate.
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