Slime Farm

Slimes only spawn in specific 16x16 chunks fixed to your world seed, underground below a certain height in dark cave-like spaces, or above ground at night in swamps under the right moon phase. Unlike most farms here, step one isn't picking a convenient spot. It's actually finding a valid slime chunk first.

Third-party seed map tools will show slime chunk boundaries instantly if you enter your world seed. The in-game alternative, digging out a flat area below Y=40 and waiting to see if slimes show up over a night or two, works but wastes a lot of time if you guess wrong. Use the map.

Once you've got a confirmed chunk, the farm is a stack of flat platforms, usually 5 to 10 layers about 3 blocks apart, filling as much of that 16x16 footprint as you can manage. Slime spawn rate scales with available floor space, so more layers means more simultaneous spawn attempts landing.

Slabs on each floor keep zombies and skeletons from stealing spawn slots, and water sweeps slimes off each layer down a central shaft, same funneling idea as a skeleton farm. Slimes split into smaller slimes when hit rather than dying outright, so most kill mechanisms use a long enough fall, or a lava-adjacent blade, to clear a whole split at once instead of chasing pieces around.

Slimeballs are a genuine early-to-mid-game bottleneck. Sticky pistons, leads, and magma cream (for Fire Resistance potions, alongside blaze powder) all draw from the same supply, so a working slime farm tends to quietly fix a friction point in a bunch of unrelated projects at once.