Nova Creeper



Nova Creepers are the most widely-known species for it's very common (and very dangerous) explosive instincts. They are as tall as Wither Skeletons, but when they detonate, the crater may lead all the way to bedrock.

Tactics
Nova Creepers are not naturally agressive mobs, but when provoked at least twice, they curl up in a ball and begin to hiss. They detonate in about 20 seconds, and depending on chance, the size of the crater may be up to 100 blocks wide. They can also detonate and leave a crater in water and lava. The initial damage from the explosion could easily kill a player, even in a full set of Diamond armor. The yellow parts on their body glow before curling up, then the Nova Creeper slowly turns white. When killed, they have a 50% chance of dropping 1-4 Nova Gunpowder.

Habitat
Nova Creepers spawn in Volcano biomes only. Even so, for every 20x20 block radius, there is only a 0.0000021% chance that they will spawn, making them extremely rare.