Minecraft wiki entry for Piston, associated text: Pistons are always placed facing toward the player. When powered, the piston's wooden surface (the "head") starts extending immediately in Java Edition; or either 2 game ticks (1 redstone tick; 0.1 seconds) later or immediately, depending on how it was powered, in Bedrock Edition. When it extends, it pushes at most 12 blocks. The piston makes a sound that can be heard within a 31×31×31 cube centered on the activating piston. Any entities in the path of the extending head are pushed with the blocks. If there is no place for the entities to go, the block pushes inside them, suffocating mobs if the block is not transparent when pushed into the eye height of the mob.