The Genei Jin (幻影陣, "Illusion Formation") is one of Yun's special attacks, introduced as his third Super Art in the Street Fighter III series. It returns as his Super Combo in Super Street Fighter IV: Arcade Edition.
Executed by performing two quarter-circle forward motions and pressing punch, Yun briefly pauses to gather his ki in a flash, with the Super Gauge turning into a timer. While the technique is active, blue afterimages of Yun follow behind him and echo everything he does split-seconds later, but they do not hit the opponent.
The move allows Yun to more easily string attacks together into combos, working very similarly to a Custom Combo. The technique itself can be started in the middle of a combo, allowing Yun to conserve his Super Gauge for when he knows it will connect.