Let them chase you, run across the plate, and jump over the pistons as they rise. Troubleshooting: Why didn't the achievement unlock?
The slimeball is the critical bottleneck in Survival mode. Slimes spawn only in specific "slime chunks" below Y=40 or in swamp biomes during certain moon phases. A verified strategy is to dig a large, flat room at Y=–30 and wait for slimes to appear. Alternatively, trading with a wandering trader or killing baby slimes (which drop 0-2 slimeballs) suffices. lovely craft piston trap achievement guide verified
Use sticky pistons whenever possible. The "lovely" part of the achievement refers to the trap's ability to reset itself. A one-time trap is crude; a repeatable trap is a work of art. Let them chase you, run across the plate,