Mala Suerte!4 (Monstruo Monstruoso)

A broad tornado crackling with spiritual pressure spins up over Karakura, leaving Keigo dumbfounded while Yumichika smiles at the sight, knowing Ikkaku has chosen to release his Bankai. Inside the storm, Edrad catches the word Bankai, and as the winds die down Ikkaku stands revealed with Ryumon Hozukimaru, two enormous blades chained to a third that floats behind him on a handle. Edrad calls it impressive, but Ikkaku tells him not to be impressed yet, only when he dies, and the two spring into the air to renew the fight.

Ikkaku's guandao carves clean through Edrad's flaming fist, then his monk's spade bites into the Arrancar's guarding forearm before a jet of shoulder-fire shoves him back. Studying the weapon, Edrad works out that Ryumon Hozukimaru grants no boost to spells, speed, or defense, only a colossal reservoir of raw destructive power, and notes that such an offense-first weapon is fragile, spotting a chunk missing from the blade. Ikkaku begins spinning the central blade so its dragon crest slowly fills, and Edrad senses the weapon's pressure climbing. Ikkaku explains that Hozukimaru is lazy and usually asleep during Bankai, so the only way to rouse its full strength is to keep trading blows, the crest reddening as it wakes and glowing fully red at peak power. Once the crest turns completely red, he asks if Edrad is ready, and the two smash together one last time in a burst of fire and spiritual energy.

Closing out Volume 23, MALA SUERTE!, in the Arrancar arc, and adapted into Episode 118, Ikkaku's Bankai! The Power that Breaks Everything. The chapter first ran in Weekly Shonen Jump as Mala Suerte!4 (Monstruo Monstruoso), meaning Monstrous Monster, but the collected volume retitled it Mala Suerte!4 (Tempestad de la Lucha), which translates as Storm of the Scuffle.