|Nuclear Fusion Grenade|
|First Appearance||The Enemy of My Enemy|
The Nuclear Fusion Grenade first appeared in the episode The Enemy of My Enemy when Octagon Vreedle used it against insane Kevin, but because of his lack of intelligence, he forgot to consider the fact that it had the power to destroy the entire Plumbers' Academy space station along with everyone in it.
This incident is mentioned by Rook, saying that he spent his last few days on Plumber training on an abandoned spaceship.
Ultimate Echo Echo then took the bomb out far into space away from the Academy and let it explode there, not harming anyone. It's used again in Basic Training in a grenade malfunction as an attempt to kill Magister Hulka.