Minecraft wiki entry for Nether_survival, associated text: Magma cubes are slime-like mobs that spawn in the nether wastes and spawn abundantly in basalt deltas, generally near lava (hence the name magma cube). They look like burnt slimes with yellow eyes, and seem to have springs under them (they jump fairly high and the "springing" is visible). Their properties are much like slimes, as killing a large one results in it splitting into 2-4 medium-sized ones, which splits into 2-4 small ones. The large and medium Magma cubes have a chance of dropping magma cream and experience when killed. You can prevent magma cubes from spawning in your base by making the floor out of transparent blocks. As mentioned earlier, you can stand on a pillar to kill magma cubes, but any ghasts or crossbow-wielding piglins might really annoy you.