This reminds me of that chapter in Onepunch Man.
The two Gremmys summon a giant meteor to destroy Zaraki and the Seiretei, and this gets everybody's attention. Everyone is concerned except for Zaraki, who leaps at the meteor. The meteor explodes into pieces, and Zaraki lands now holding a giant axe.
Pretty predictable chapter. So Zaraki's bankai is a giant axe? I guess it suits him, since all he cares about is how to cut people and things up. Obviously Zaraki is not going to lose at this stage. We'll see if the Gremmys have any more tricks left, but Zaraki will murder them sooner or later. Perhaps Zaraki's bankai will have a new ability or two as well.