WHat are the criteria for determining if a character can use Busoshoku haki.
Sanji has never shown Busoshoku Haki, yet he's there.
Neither has Mihawk, yet he's not there.
Sanji was named a possible candidate to fight Caesar Clown, a Logia user, since he has Haki. This can only refer to Buso haki. The criteria are very simple: has there been mention or visible showings of that person using clear Buso haki? If yes there counted as such.12:35, June 19, 2016 (UTC)