
Monkey D Luffy’s WANTED poster with a reward of 400 million Berries.
THE ULTIMATE ONE PIECE BOUNTY ARCHIVE
New bounty, issued after Marineford. It also covers the progress made since Enies Lobby: Thriller Bark, Sabaody, Amazon Lily, and Impel Down. It stays in force until the end of Dressrosa: from the two-year timeskip to Punk Hazard, by way of Fish-Man Island.

Monkey D Luffy’s WANTED poster with a reward of 400 million Berries.

Luffy earned this one by losing.
The first three bounties tracked wins — Arlong Park, Alabasta, Enies Lobby. The 400 million arrives after Marineford, the single worst outcome of his life: he broke into Impel Down, cracked Level 6 open, walked into Marine Headquarters in front of all three admirals, and left without Ace.
What moved the number wasn't the body count. It was the fact that the war went out live, and the world found out who he was — the son of Monkey D. Dragon, the most wanted man alive, and the grandson of Vice Admiral Garp. Overnight, Luffy stopped being a promising rookie and became a hereditary problem. Four hundred million isn't a measure of his strength. It's a measure of his surname.
Which is also why the jump looks oddly small. Enies Lobby had been worth +200 million; Marineford, somehow, only +100. The World Government had just buried Whitebeard, executed Ace, and lost control of its own execution platform on camera. Pricing the kid who lit the fuse any higher would have meant publishing the size of the damage.
The poster then had a strange afterlife. For the two years the Straw Hats were scattered, that 400 million portrait was the one Demalo Black and his crew of impostors used to recruit on Sabaody Archipelago — so when the real Luffy came back, someone else had been wearing his face for months. It's also the bounty he was carrying when Brownbeard, a former pirate captain met on Punk Hazard, spelled out the label now stuck to his whole cohort: the Worst Generation, the eleven Supernovas who were on Sabaody on the eve of the war, plus Blackbeard.