The bug
Zombies of a village siege spawn even if the gamerule doMobSpawning is turned off.
How to reproduce
Village sieges only happen
when the moon is at the zenith
when a player (not being a spectator) is nearby
when no second village is close
when the village has at least 10 doors
when the village has at least 20 villagers
with a chance of 1 / 10
Because a siege only happens with a chance of 1 / 10 it is easier to cause one by having a clock (for example repeater) setting the time to day, waiting a short moment (for example one redstone tick), setting the time to 18000 and then waiting a little bit longer.
Create a Superflat world with the preset "Classic Flat"
Turn the gamerule
doMobSpawningoff/gamerule doMobSpawning falseGet to a nearby village, for example by using
/locate Village, and wait
Linked issues
is duplicated by 4
MC-155176
Zombie Sieges Spawn when doMobSpawning is false
Resolved
MC-156001
doMobSpawning set to false doesn't stop zombies from spawning by villagers.
Resolved
MC-156295
Zombie raids still occur when the gamerule doMobSpawning is disabled
Resolved
MC-156497
Zombies spawn in night time when villagers are near even though the /gamerule domobspawning is false
Resolved
I don't know if it's worth mentioning anymore, but they also spawn with these conditions in peaceful. I saw a bunch of zombies trying to spawn in with mab spawning false and on peaceful.