Bakudantsuki (爆弾突き, Bomb Thrust) is a technique of Kensei Muguruma's Zanpakutō, Tachikaze.
Kensei infuses Tachikaze with Reiatsu, causing it to glow, until it takes the shape of a glowing orb, at which point he fires it as an energy blast with extreme force. This blast is quite devastating, blowing off the arm of Ichigo's Full Hollow form. Kensei later uses it to destroy a Gillian simply by using the ability while impaling the mask of the Hollow with the blade of Tachikaze, which completely obliterated the Gillian's head.
↑Bleach Official Character Book UNMASKED; page 152