What is the name of Guile's upward kicking special move?

Guile’s upward kicking special move is called the Flash Kick.

The Flash Kick is a rising somersault kick in which Guile launches himself backward into the air while striking with an extended leg. In the classic Street Fighter control scheme, the player performs it by charging downward and then pressing upward plus a kick button. Because the move is invulnerable or highly effective against airborne opponents in many versions, it became one of the series’ most recognizable anti-air attacks.

The technique’s original Japanese name is Somersault Kick, and that name is still used in some games, translations, and move lists. “Flash Kick” is the familiar English name associated with Guile. His other iconic special move is the Sonic Boom, a horizontal projectile created by charging backward and then pressing forward plus punch.

Guile debuted as one of the eight playable World Warriors in the original 1991 Street Fighter II. His charge-based moves helped establish a distinctive defensive play style built around holding positions, controlling space, and punishing opponents who jump in.