Rainbow Slime

The Rainbow Slime is a hardmode monster that spawns in any hallowed biome. It can only spawn while it's raining, or during a blizzard if you're in a hallowed Snow Biome. The conditions make it a somewhat rare monster, though it's easy to encounter it if the conditions are right. Its color shifts constantly, as do the Rainbow Bricks it drops.

Tips

 * If you're looking to find a Rainbow Slime, go to a hallowed biome nearby if it's raining during a Blood Moon. Chances are you will encounter at least two during the night. Only do this if you are well into hardmode, or else you will likely end up dying fairly quickly.