Unlock Characters (VS Mode)
Crocodile - Beat him in normal mode (island 1).
Doflamingo - Beat him in normal mode (island 4).
Edward Newgate (optional boss) - Beat him in normal mode (island 3).
Final Boss - Beat him in normal mode (island 5).
Final Boss (second form) - Beat him in Hard mode (island 5).
Garp (optional boss) - Beat him in unlimited mode (island 4).
Human Lucci (optional boss) - Beat him in normal mode (island 2).
Kaku - Beat him in normal mode (island 3).
Kid - Beat him in normal mode (island 1).
Kizaru - Beat him in normal mode (island 4).
Leopard Lucci - Beat him in normal mode (island 3).
Mihawk - Beat him in normal mode (island 2).
Pauly (optional boss) - Beat him in normal mode (island 2).
Shanks - Beat him in normal mode (island 2).
Smoker - Beat him in normal mode (island 2).
UC1 Bosses - Have a UC1 save with all the bosses unlocked or finish UC2 Boss Rush (unlimited difficulty only).
Vivi (optional boss) - Beat him in normal mode (island 1).
Unlock Survival Mode
Finish the game in normal mode.
Unlock Boss Rush Mode
Must be in unlimited mode and collect the map pieces from the UC1 bosses that appear at some points in the game in this difficulty. You must defeat the bosses with the fury boost or he wont drop the map piece.