Jichinsai is a move used by Heihachi Mishima since Tekken 6: Bloodline Rebellion.
Description[]
Heihachi performs a wide axe stomp with his left foot. The move has an extremely low hitbox and can hit grounded foes, making it a good mixup with his Geta Stomp (which hits low instead of middle).
In Street Fighter X Tekken, it was his Cross Art. Heihachi starts up with a gut punch followed by a Hammer Punch and a wide axe stomp before he grab and throw his opponent out.
In Tekken 8, while Heat is active, pressing 2 after the attack will execute Thunderous Battering Ram after the stomp and flip the opponent on their face. The full string name is Rending Battering Ram. This move can also be done from the Thunder God's Kamae stance.