The Shitenshuu (死点咒 Shitenshū, "Death Point Curse") is one of Gen's Super Combos in the Street Fighter Alpha series in his Mantis style, exclusively to his A-ISM Super Combo Gauge its notably the only super move/attack in the Alpha series to use poison.
Executed by performing two quarter-circle backward motions and pressing punch while using the Mantis style, Gen draws back on a single-leg stance, winding up his arms in a focus with poison and then launches a flurry of Hyakurenko strikes, ending with a pressure-point jab with his index and middle finger from his following hand. If the finger jab connects, the opponent receives poison damage and a timer begins to count down above their head.
For each second that counts down, the foe will take a chunk of damage. If the timer reaches zero before the opponent is able to land a blow on Gen, then they are stunned. This allows Gen to follow up with any attack or combo he likes.
The attack likely inspired the Shitenketsu Ultra Combo Gen uses in Super Street Fighter IV; though similar in concept, instead of requiring Gen to prevent his opponent from landing a hit within a certain period, it usually requires Gen to land another hit within a certain period.
It can be comboed into after a crouching light kick if Gen is close.