The Gekishouhadouha (激掌波動波, literally Violent Palms Breaking Wave) is one of Reiji Oyama's special techniques, having appeared in every game he has appeared in. Its animation and appearance tends to differ from various games he's been in.
In the first Power Instinct, Reiji would form the ball of energy in his hand before thrusting it forward with his other hand at the opponent. In Power Instinct 2 and Power Instinct Legends, Reiji would sweep his arm through the air as he launched the projectile at the opponent. During latter two games, the projectile was a lightning-type of projectile. Since Power Instinct Matrimelee, it is more of a fireball and would set the opponent aflame for a moment when it successfully connected.