Air dodging

Air dodging is a technique in SSF2 that allows the player to avoid attacks for a few frames while in mid-air. It's performed by pressing the shield button while in the air. During an air dodge, a character will temporarily receive Invincibility frames while flashing white. Characters will receive increased gravity due to no air acceleration from performing the dodge.

Air dodging is not present in Super Smash Flash and was first introduced in SSF2. It functions similar to how it works in Super Smash Bros. Brawl and Super Smash Bros. for Nintendo 3DS / Wii U, however, as of v0.8a, characters cannot air dodge out of hitstun nor tumbling which makes air dodging a little more situational.

Controversy
The way air dodging works in SSF2 has generated debate in the community, with people against it advocating for directional air dodging (much like in Melee) in order to grant the player more movement options (such as wavedashing and wavelanding) and thus speeding up the game play.

Defenders of the mechanic state that the current air dodges makes the game unique and different from the aforementioned games while being riskier and less abusable than the air dodges in Brawl (and to a lesser extent in SSB4).