Radioactive Hydra is a monster in AdventureQuest Worlds.
The Radioactive Hydra is the result of a normal Hydra swallowing a Plutonium core. The players had to slay the Radioactive Hydra in order to get the Plutonium core out of it so that Laken can use it for a portal to the World Soul's part of the Underworld.
- Location: World Soul
- Level: 50
- HP: 75,266
- MP: 100
- Guardian Shard
- Treasure Chest
- Radioactive Hydra is a recolored version of Styx Hydra.