Radscorpion

Radscorpions are an extremely large version of the North American Emperor scorpion, mutated by radiation. Contrary to some expectations, their poison grew more potent, not diluted. They are nocturnal and sensitive to light. Samples of poison from their tail can be used to make antidotes.

Appearances in Fallout games
Radscorpions can be encountered in all Fallout games.