In its crossover appearances, Ken and Sakura can use the move as well, and in X-Men vs. Street Fighter, Marvel Comics character Rogue can also use this technique by using her Stolen Power special attack on Akuma.
It is executed the same as a regular Hadoken, albeit in midair. The user thrusts their hands and fires an airborne Hadoken, angled down.
The angle is usually about 45° downwards, and the speed at which the fireballs fall depends on the strength of the punch button pressed, with the weakest going slower, and the stronger falling faster. In Street Fighter IV, the angle of Hadoken also depends upon the punch button used. The visual execution varies between games, in which some games depict Akuma pausing in air to throw both fireballs before falling back to earth while in others he throws both fireballs fluidly during the fall.
The Zanku Hadoken is great for stopping close-range counters while in the air and assaulting grounded foes. However, in some more aerial-oriented games, the angle throw sometimes makes the Zanku Hadoken unsuitable for air-to-air combat.