Boost Kick

Boost Kick (, Boost Kick) is Zero Suit Samus's up special move in Super Smash Bros. 4 and Super Smash Bros. Ultimate.

Overview
Zero Suit Samus performs a jet-propelled split-legged side kick that ends with an outside crescent kick, giving it appearance somewhat similar to Fire Wolf. It is a considerably more reliable recovery option than her previous up special move, Plasma Wire, due to its noticeable faster speed, while not requiring timing and spacing due to it not being a tether. In addition to this, it is a potent KOing option as well as a very effective out of shield option, KOing at around 85%-110% or earlier if her opponent is close to the blast line. It is typically used as a combo finisher after a down smash or multiple up aerials. However, it is somewhat easy to escape from the move via Directional Influence, especially if the victim is at a high percent.

Customization
Special Move customization was added in Super Smash Bros. 4. These are the variations:


 * 1) Boost Kick: Default.
 * 2) Impact Kick: Launches opponents skyward with a jump kick, spinning finisher is extremely powerful.
 * 3) Lateral Kick: Lowers the boost on her heels and performs a low jump kick, uses extra strength to boost forward.

Origin
Boost Kick and the Jet Boots are unique to Smash, and has no presence in any Metroid game. According to Masahiro Sakurai, however, they were added for balance purposes to increase Zero Suit Samus' physical strength. In addition, Boost Kick was likely implemented to remove up special tether recoveries in SSB4, which also applied to (who received Winged Pikmin) and Ivysaur (who was cut).

There are similar upgrades in the Metroid games that have similar concepts to the Jet Boots like the which is exclusive to the 2-D styled Metroid games, the Jump Boots which only appears in ' and the  from the ' series.