Chests and anvils can be manipulated as they dont have a fixed collision hitbox. Standing against an anvil and looking a different anvil thats rotated will cause the hitbox of the anvil ur against to change to the one ur looking at clipping your hitbox inside the anvil. Same thing happens with chests. https://www.mcpk.wiki/wiki/Anvil/Chest_Manipulation
Chests and anvils can be manipulated as they dont have a fixed collision hitbox. Standing against an anvil and looking a different anvil thats rotated will cause the hitbox of the anvil ur against to change to the one ur looking at clipping your hitbox inside the anvil. Same thing happens with chests. https://www.mcpk.wiki/wiki/Anvil/Chest_Manipulation