How does Buggy become a warlord?

Buggy was invited to become a member of the Seven Warlords of the Seas, after it was revealed that he was a member of the former Pirate King’s crew. This greatly increased Buggy’s prestige in the pirating world and he used his cunning abilities to recruit strong pirates.

Is Buggy warlord level?

9 Weakest: Buggy Although he’s got decent powers up his sleeve, Buggy is still quite weak in comparison to some of the other Warlords and is nowhere near their level.