

It is important to light the spawn platforms up, otherwise other hostile mobs can spawn too. Spawning pads are usually constructed with a 2½-block gap using slabs, to allow all types of slimes to spawn. In most farm designs, spawning platforms are created which spawn slimes that are then moved to a killing trap, usually a drowning trap to split larger slimes down and dispatch the smallest size.

The first step in constructing either farm is the spawning place. This method has the advantage of not requiring a dug-out room prior to building the farm, and the size of the farm is not limited, unlike the slime-chunk method. Slime spawning in swamps can occur between Y=51 and Y=69 inclusive. This method requires an underground room to be dug out before the farm is constructed. Within slime chunks, slimes can spawn up to Y=39 inclusive.

Every chunk that is generated in a world has a 10% chance of being a slime chunk.
