Hydro Pump

Hydro Pump (, Hydro Pump) is Greninja's up special move.

Overview
Greninja uses water to propel itself upward, in a manner similar to 's Quick Attack in that it can change directions while it moves. However, unlike Quick Attack, the move can move twice the distance in a single direction, is a little slower, and carries most of the momentum gained, which gives it better maneuverability than Quick Attack does. Hydro Pump also deals slight damage with decent knockback and does not cause flinching, which can be used to gimp. While it offers excellent distance, Greninja will immediately start falling once the second water stream ends, which can often cause inexperienced players to underestimate the vertical distance gained from this move. It will also cancel if Greninja bumps into a wall, sending it into a tumble. If this happens, Greninja will no longer be able to use jumps or Shadow Sneak, or reattempt another Hydro Pump until cancelled by landing or with an aerial, Water Shuriken, or Substitute. Greninja is still capable of wall clinging, and thus wall jumping, and is its only means of recovery in this scenario (though Substitute grants mobility if successful). Unlike typical tumbling, Greninja does not need to tech in order to prevent crash landing, and can act immediately as though they had fallen normally.

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


 * 1) Hydro Pump: Default.
 * 2) High-Capacity Pump: Greninja shoots more controllable water pumps, but the move is slightly slower and doesn't do damage.
 * 3) Single-Shot Pump: Greninja only shoots one pump, but it's more powerful. It gains about 30% more distance.

Use by other Pokémon

 * Blastoise - When summoned as a Poké Ball Pokémon in SSB and Melee, Blastoise uses Hydro Pump in a horizontal direction.
 * Kyogre - When summoned by a Poké Ball, Kyogre uses Hydro Pump with free range horizontally. Unlike other Hydro Pumps, Kyogre's Hydro Pump doesn't do any damage, instead pushes opponents or objects.
 * Squirtle - When its trainer activates Triple Finish, Squirtle uses Hydro Pump as part of the Final Smash.

Origin
Hydro Pump is a powerful special Water-type move with 120 (110 starting with Generation VI) base power but has 80% accuracy that was introduced in Generation I and was considered the strongest Water-type move before Generation III.

Greninja like other Water-type starters is capable of learning this move by leveling up. Hydro Pump is described as "blasting the foe with huge volume of water launched under great pressure" and is usually depicted as a single, large torrent of water launched at the foe, contrary to Greninja's usage in SSB4 which involves riding two thin jets of water in the style of the Smash version of Quick Attack (which has a Pokémon series Water-type variation known as Aqua Jet which Greninja can't learn).

Trivia

 * Hydro Pump is one of three up special moves that always uses up the character's double jump in Smash 4 regardless if the player saved it before use, despite the near-universal change across all other characters that allows them to use their double jump after their up special move if they are hit out of it. The other two up special moves are Quick Attack and Spin Attack, which also have this quirk in Brawl.