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Rocketbarrel Boost (Boostum Highus) is an attack that Diddy Kong can utilize once he drinks one of Cranky Kong's potions in Donkey Kong 64; once Diddy jumps into a barrel with his face on it, he will gain the Rocketbarrel Boost and be able to fly around using his Jetbarrel (also known as Barrel Jet or Rocketbarrel Pack). This attack utilizes Crystal Coconuts as fuel. However, this ability is also barred in a few sections of the game. In both Mario Power Tennis and Mario Hoops 3-on-3, Diddy is also capable of using the Rocketbarrel Boost to fly.
Diddy Kong also uses Rocketbarrel Boost in the Super Smash Bros. series. Rocketbarrel Boost is Diddy's up special move, and allows him to fly with only his jetpack. Diddy Kong can charge this attack up, and if it is charged, he will be able to fly farther. Tilting the control stick allows Diddy to curve his flight path, allowing him to fly in several different directions. Diddy Kong can ram into opponents to damage them, and if used in mid-air the initial burst of height acts as a meteor smash. However, if Diddy Kong is attacked while flying, he will lose his jetpack, and fall down. The jetpack will then fly away, and has a chance of hitting another player. In Super Smash Bros. for Nintendo 3DS and Super Smash Bros. for Wii U, two custom variants can be unlocked for this move. The first one is Rocketbarrel Attack, which deals more damage when Diddy hits an opponent, but his flight path cannot cannot be controlled as easily. The second is Rocketbarrel Kaboom, which charges faster and can be steered easier, but doesn't travel as far and explodes if it hits terrain. The Rocketbarrel Boost is also used during Diddy Kong's Final Smash, Rocketbarrel Barrage.
While Diddy does not use this specific move to fly, he does utilize the Barrel Jet to hover in Donkey Kong Country Returns and Donkey Kong Country: Tropical Freeze, as well as use it as a Power Shot in Mario Power Tennis and as a Special Shot in Mario Hoops 3-on-3.
Super Smash Bros. for Nintendo 3DS / Wii U
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