Thunder (Pikachu)

Thunder is a recurring attack in the Pokémon games which is usable by Pikachu in the Super Smash Flash series.

Overview
Thunder's effects are self-explanatory: Pikachu generates a large lightning bolt with infinite range from the sky that comes falling directly towards Pikachu's position.

In Super Smash Flash
In the original Super Smash Flash, Thunder is both 's down attack and. The bolt comes down and passes through Pikachu, continuing to move way beyond the floor. When used on the ground, it deals a set of 9% damage per frame and heavily launches opponents on contact. If Thunder is initiated in the air, Pikachu becomes an actual hitbox while both Pikachu and the bolt deal 4% with less knockback, which means Pikachu can deal damage by itself even before the bolt comes down; the aerial version can also be held indefinitely with the attack key, without needing to pick an item as the ground version requires.

In Super Smash Flash 2
For the reboot, Super Smash Flash 2, Thunder has become 's down special move and has been upgraded to match its official counterpart from the Super Smash Bros. series, amalgamating several attributes from the latter. The bolt now crashes down upon entering in contact with Pikachu, rather than passing through it as it does in SSF, dealing 28% electric damage and massive knockback to anyone near Pikachu and the bolt. The bolt itself also deals 11% electric damage and moderate knockback by itself, and it will stop when hitting a platform. It will also be blocked by certain ceilings. Pikachu is given horizontal mobility (if in the air) during the animation of the attack, and if the bolt strikes him while in the air, he will gain a slight vertical rise.

Origin
Thunder is a damage-dealing Electric-type attack that was introduced in the Generation I Pokémon games, Pokémon Red and Blue. The attack consists of the user summoning a bolt of lightning from the sky onto their opponent, is regarded as one of the strongest of all Electric-type moves in the series, albeit with low accuracy. Pikachu can learn Thunder at rather high levels, and it can also be taught the move with TM25. The power of Thunder is evidenced by the high damage and knockback it is able to deal in the SSF games.

Trivia

 * Prior to SSF2 Beta, the bolt of lightning was able to meteor smash opponents hit. This has since been removed and passed along to 's variant of Thunder.