Problem
Mobs or players standing on block, attached with double sticky piston facing upwards, cause them to glitch through blocks. This happens even if there's no ceiling blocks obstructing them.
How to reproduce
Build a contraption shown on images.
Place any mobs or minecart on the block where sticky pistons will push up
Power the contraption.
❌ Mobs and minecart remains underneath the block, represented by image.
What to expect
Entities should be on top of the gold block in the image after running.
Test
This bug is tested in Minecraft 1.16.5 and Minecraft 1.17 vanilla. Simulated in The Void preset(superflat) and 2 default worlds.
Related issues
Attachments
Comments
migrated
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If this bug is fixed, won't it provide an additional way for players to glitch through the bedrock ceiling in the Nether?
migrated
I don't think that follows from this bug. This bug happens when two pistons rapidly extend, even if there's no ceiling obstructing them.
migrated
@unknown You use zero-ticking?
Some people in the community would not be happy if Mojang would remove those.
Rephrased: The bug showcased here that entities fall through blocks has a different cause to what's in your title and bugpost description.
An example of entities falling through blocks that is piston-specific is MC-197226, you don't have to zero-tick the pistons, but have to have a block above the entity.
[Mod] Jingy
Can confirm in 23w41a:
[media]
[Mod] Jingy
This looks to actually duplicate MC-159503, just with a double piston setup instead of a single piston.