Basically when entering a woodland mansion, all the vindicators and neutral and become hostile when you hit them. This does not affect the evokers, they are hostile on sight. I have encountered this bug in the ''spooky mansion'' seed using the seed picker while creating a new survival world. I went into the woodland mansion and noticed that none of the vindicators were attacking me. Until I hit them... This only affects the vindicators inside the mansion and not the ones spawned by spawn eggs (I tried and they killed me!)
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However, this issue has been closed as a Duplicate of MCPE-43208.
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