18. Phazon Beam
Metroid Prime series
Some will argue that Metroid Prime's Phazon Beam is actually the same as Super Metroid's Hyper Beam, when in reality the Phazon Beam is way cooler. They're both hyper-powerful endgame weapons, but where Super's Hyper beam shoots rainbows up Mother Brain's pee-hole, the Phazon fires totally nuts, radioactive-ish energy in an immensely powerful stream. The most powerful version is in the first Metroid Prime, where you actually have to be standing in a puddle of the last boss's gooey secretions to even use it.