Slime Spawning Respects Light

Vanilla green slimes normally ignore light entirely and spawn only by location, such as in swampland and in "slime chunks" below Y=40, so an underground base within such chunks, even if well-lit, will still have to deal with them spawning in it. This mod simply prevents any vanilla green slime from spawning on a spot that has an artificial (as in, from torches or such) light level of 8 or higher, the same check done by most other monsters like zombies. Other types of slimes, like magma slimes or modded-in slimes, are not affected, and sunlight is ignored so they should still spawn normally in that case (though this needs further testing).