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Complete Battle Royale in the Thousand Arena under the Hard difficulty setting with five characters.

Successfully complete all levels.

Complete the indicated task to unlock the corresponding character.

Akainu: Complete Training and 4-man Battle Royale with him.
Aokiji: Complete Training and 4-man Battle Royale with him.
Brook: Complete Sabaody "The Start Of An Adventure" with Luffy (Brook).
Chopper: Complete Training and 4-man Battle Royale with him.
Cobby & Herumeppo: Complete Training with twelve characters.
Eiichiro Oda: Complete Land Festival "What If The Eagle Lands On The Ring Into The Sea" with Jinbei (Camie, Arlong and Hatchan).
Franky: Complete Sabaody "A Little To Go Blind" with Luffy.
Garp: Complete Last Resort "Nogadobatoru" with Luffy.
Kizaru: Complete Training and 4-man Battle Royale with him.
Luffy: Complete Training and 4-man Battle Royale with him.
Nami: Complete Training and 4-man Battle Royale with her.
Pandaman: Remain idle at the map selection screen and tap the boat that sails by, then complete that mission.
Robin: Complete Amazon Lily "Oh, That's It I'm... Happy" with 30% HP.
Sanji: Complete Training and 4-man Battle Royale with him.
Sengoku: Complete Last Resort "Before The Last Great Barrier" with Ace.
Sentoumaru: Complete Marine Ford "Army vs. Bear" with more than 25% HP.
Smoker: Complete all objectives in East Blue mission level 43 in the center.
Tashigi: Complete 1-man Battle Royale with ten characters.
Usopp: Complete Training and 4-man Battle Royale with him.
Zoro: Complete Training and 4-man Battle Royale with him.