Instant Transmission

Instant Transmission (瞬間移動, Shunkan Idō) is Goku, Kaiō-ken Goku, and Super Saiyan Goku's up special move in Super Smash Flash 2. Goku performs a flip kick before teleporting in the direction inputted by the player. The move has a fairly fast start-up time and intangibility frames during the teleportation.

The kick at the start deals 12%, considerable vertical knockback and slight horizontal knockback depending on which hitbox connects. With its speed and good knockback scaling it can turn into a good KO tool, especially against floaties. If Goku is in Kaiō-ken mode it does 14%, and is slightly faster.

Super Saiyan version
Super Saiyan Goku's Instant Transmission is very similar to standard Goku's but has some different properties: it goes a shorter distance, only deals 10% and less knockback, always launches straight up, does not cause helplessness nor lag if landing on the ground and can be done repeatedly in the air. Additionally, by holding the special button Goku will perform a kick upon reappearing and if held longer he will follow up with a strong meteor attack. Both hits deal 10%.

Trivia

 * In v0.9a Goku teleported the opponent with him if the initial kick connected, finishing the move with another kick. According to gameplay footage, Instant Transmission in SSF2 Beta would work in a similar way.
 * In v0.9b, there was a glitch that caused Goku to fly very far after executing Instant Transmission as Kaiō-ken finished, often leading to SDs or giving Goku a very large extension to his normal recovery.