It's so insane to me that, going into this arc, I figured it would be a light exposition-heavy arc before the more intense final arcs. The Straw Hats find about the Seraphim (clones of the Warlords with genetic traits from other species), have a token fight against Cipher Pol 0 (a government agency that they've already fought before)...
...and then a Buster Call was declared on the island, and an Admiral (one of the most powerful members of the Marines) showed up.
And he brought one of the Five Elder Stars with him. The group is so mysterious that they were introduced roughly 900 chapters ago and, despite being the leaders of the World Government
supposedly, they didn't even have their names revealed until very, very recently.
That alone would make this arc much more of an uphill struggle than I expected, but then, Vegapunk (a sympathetic scientist who turned to the World Government for funding) set up a global announcement to reveal some kind of dark secret that the World Government really does not want to get out, to the point where they would murder every single person on an island, burn the island to the ground, and paint its inhabitants as crazed murderers because a handful of scholars were studying that period of history.
This leads to a double page spread that it feels like Oda has wanted to do for a long time:
(using a fan translation since I can't copy/paste double page spreads from the official scans as one full image)
There's no reaction shots from other characters, no dialogue - just the Five Elder Stars/Planets, fully transformed (previously, they'd only ever transformed once, with their forms being hidden in shadow) and out for blood in a desperate attempt to stop something that they've kept secret for 800 years from being revealed. These characters have been around for over
twenty years real-time and have been one of the biggest mysteries of One Piece (it's unclear what's going on with them - flashbacks to 40 years before the events of the series have them looking identical to how they look now). I figured that they'd be politicians, running the government but leaving the fighting to the Marines, before this arc (and the recent Sabo flashback that showed their shadowed transformations), so this shot is incredible for me.
It's hard for me to put into perspective how insane this is if you're not familiar with One Piece, but it's kind of like the "Avengers Assemble" scene in Avengers Endgame, except the tone is reversed because it's the top villains of the series who are all showing up because they desperately want to stop Vegapunk, with Luffy (the main protagonist) standing in their way. (Luffy's the little guy in the foreground) It would be like if, midway through a Legend of Zelda game, all of the bosses attacked you at once.
This arc has turned into some end-of-series levels of chaos and escalation, which has me wondering how crazy the finale of the series is going to get if this is just a preview.