Sticky Piston is crafted by combining a regular piston with a slimeball on the crafting grid. The slimeball coats the piston head with adhesive, transforming a one-way pushing device into a bidirectional one. When powered, the head extends and pushes the block in front; when the signal cuts, the head retracts and brings the pushed block back to its original position.

This sticky behaviour is what makes hidden doors, drawbridges, mob trap retraction systems, and most flying machines possible. Without this variant, every retracted block would simply be left dangling at the new location. As with the regular version, certain blocks resist push entirely — obsidian, bedrock, blocks with tile entities — but anything else can be moved up to twelve units. One important caveat: if the head pushes another block in a chain, only the directly-attached one returns; further blocks stay where they were placed. This is why slime blocks and honey blocks (which group together) are such popular companions.