Magma Cube

The Magma Cube is a hostile Mob that spawns on the Crimson Isle.

Crimson Isle
Magma Cubes naturally spawn in the on the Crimson Isle.

Private Island
In Stranded, slimes can be turned into Magma Cubes by lighting them on fire. This can be done by using a, , ( also works) or a weapon with the  Enchantment.