One Piece: Grand Battle - Very hard mode

Voice collection:
Successfully complete Event Battle to unlock that character's voice collection at the "Treasures" menu.

Zolo's fourth costume:
At the "Press Start" screen, hold R, then press Down, X, Down, X, B, A2, Y to unlock Zolo's fourth costume.

Zoro's third costume:
At the "Press Start" screen, hold L, then press Down, A, Down, A, B, A, Y to unlock Zoro's third costume. In the Japanese version, hold L, then press Down2, A, B, A, Y at the "Press Start" screen.

Alternate costumes for The Straw Hats:
After unlocking Shanks and Mihawk, successfully complete the entire move set for all The Straw Hat Pirates in Training mode to unlock a third costume for them inspired by the Color Walk books. After unlocking the third Straw Hat costumes, successfully complete Grand Battle thirty times or Event Battle six times, with each of the Straw Hat crew to unlock a fourth alternate costume.

Alternate title screen:
Unlock all the characters to get a new title screen that features everyone.

BMG Select:
Successfully complete Event Mode with Mihawk on the hard difficulty setting to unlock the "BMG Select" at the "Treasures" menu.

Chopper's fourth costume:
At the "Press Start" screen, hold R, then press Left, A, Right, X, Y, Left, Right, B to unlock Chopper's fourth costume.

Chopper's third costume:
At the "Press Start" screen, hold L, then press Y, Left, Right, A, Up, A, Down to unlock Chopper's third costume. In the Japanese version, hold L, then press Left, Right, A, B, A, Y at the "Press Start" screen.

Davy Back Fight mini-game unlockables:
Win the Davy Back Fight min-game the indicated amount of times to unlock the corresponding bonus:

Groggy Ring: 4 times
Donut Race: 10 times
Crash Rush Boxer the box breaking: 18 times
Snow getting rid of snow: 26 times
Breaking Krieg's Armor: 29 times
Sanji & Zoro voice announcing: 33 times; also need all support character voices unlocked
The "Fix" sign: 34 times

Ending movies:
Successfully complete Event Battle to unlock the ending movie at the "Theater" menu.

Extra moves:
To get extra attack add-ons for Luffy's Gum Gum Scythe attack, you must have over four fruits when using this attack. Once you attack, after your opponent hits the wall press X and you will hit your opponent in the air. Then, keep pressing X. You will do another add-on. You will hit them in the air. Then, keep pressing X. For the final attack add-on, you will hit them up again. Luffy will count down to "1" then he will yell and twist like a spiral, bounce up, and smash your opponent through the roof of the building. If you KO your opponent while doing this trick you will see the building fall around Luffy and he will say, " I'm gonna be King of the Pirates" and you will win. Note: This trick works well with over four fruits and if your opponent health is down slightly past halfway.

Extra System Voice:
Win all three rounds of Usopp's Pirates' Challenge to unlock the announcer as a System Voice.

Gallery:
Successfully complete Event Battle to unlock that character's images in the gallery.

Luffy's fourth costume:
At the "Press Start" screen, hold R, then press Up, X, Up, X, B, A2, Up to unlock Luffy's fourth costume.

Luffy's third costume:
At the "Press Start" screen, hold L, then press Up, A, Up, A, B, A2 to unlock Luffy's third costume. In the Japanese version, hold L, then press Up2, A, B, A2 at the "Press Start" screen.

Marine HQ stage:
After unlocking everyone, successfully complete their move lists in Training mode. After doing so, destroy all the pillars in the stage. Do this with every character to unlock the stage.

Maxim stage:
Successfully complete Event Battle with Enel to unlock the Maxim stage.

Mr. 2 Bon Clay's secret attacks:
Instead of holding L and pressing A B to use a random clone-clone attack, try the following moves to transform instead. By doing this, you can use strategy instead of luck for which character you will transform into.

Mr. 7: While holding L, press A4, B.
Mr. 8: While holding L, press A3, B.
Mr. 9: While holding L, press A2, B.

Nami's fourth costume:
At the "Press Start" screen, hold R, then press Left, X, Left, X, Y2, B, Down to unlock Nami's fourth costume.

Nami's third costume:
At the "Press Start" screen, hold L, then press Left, A, Left, A, B, A, Y to unlock Nami's third costume. In the Japanese version, hold L, then press Left2, A, B, A, Y at the "Press Start" screen.

Play as Aokiji Japanese version:
Successfully complete Event Battle with Luffy, Zoro, Nami, Usopp, Sanji, Chopper, Robin, Buggy, Kuro, Krieg, Arlong, Smoker, Bon Clay, Crocodile, and Foxy. Then, play Event Battle again with Luffy. In the final stage you will battle Aokiji. To unlock Aokiji, you must use your level 2 special.

Play as Arlong:
Successfully complete Event Battle with Nami to unlock Arlong.

Play as Bon Clay Japanese version:
Successfully complete Event Battle with Chopper to unlock Bon Clay.

Play as Buggy:
Successfully complete Event Battle with Zoro to unlock Buggy.

Play as Choppy:
Unlock Ms. Sunday, then successfully complete Event Battle or Story mode with Luffy, Nami, or Sanji on the hard difficulty setting to unlock Choppy.

Play as Crocodile:
Unlock characters one through fifteen. Then, successfully complete Story mode on all four difficulty settings with all those characters. Then, successfully complete Story mode with Luffy on the very hard difficulty setting. When facing Crocodile, defeat him with a Secret attack to unlock him in Story mode. Successfully complete Story mode with Crocodile to unlock him in all other modes. In the Japanese version, successfully complete Event Battle with Robin.

Play as Don Crick:
Successfully complete Event Battle with Sanji on the normal difficulty setting to unlock Don Crick.

Play as Enel Japanese version:
After completing Event Battle with Luffy, Zoro, Nami, Usopp, Sanji, Chopper, and Robin, complete their move list in Training mode. A picture should flash by of Enel challenging you. Then, play a regular tournament at Grand Tours Tournament mode. One of the character will be replaced with Enel. Defeat and win the tournament.

Play as Foxy Japanese version:
Successfully complete Event Battle with Chopper twice to unlock Foxy.

Play as Hawk-eyes Mihawk:
Unlock Red-haired Shanks, then successfully complete Story mode with Roronoa Zolo on the very hard difficulty setting. Use a secret attack to defeat Hawk-eyes Mihawk to unlock him. In the Japanese version, successfully complete Event Battle with Zoro on the very hard difficulty setting after Shanks has been unlocked unlocked. Defeat Mihawk with a level 2 special after getting hit with Mihawk's level 2 special to unlock him.

Play as Krieg:
Successfully complete Event Battle with Sanji to unlock Krieg.

Play as Kuro:
Successfully complete Event Battle with Usopp to unlock Kuro.

Play as Mr. 2 Bon Clay:
Unlock characters one through fourteen, including Ms. Sunday, Tony Tony Chopper, Red Haired Shanks, and Hawk-Eye Mihawk. Then, use Sanji in Story mode on any difficulty setting. During the ending credits, hold L and press A2, X, A, Left, A, X, B, A, X, Y, X, A, R2, Left to unlock Mr. 2 Bon Clay.

Play as Red-haired Shanks:
Unlock Tony Tony Chopper, the successfully complete Story mode with Luffy on the very hard difficulty setting to unlock Red-haired Shanks. In the Japanese version, successfully complete Event Battle with Luffy on the very hard difficulty setting after unlocking Aokiji and Enel.

Play as Smoker:
Successfully complete Event Battle with Luffy to unlock Smoker.

Play as Tony Tony Chopper:
Unlock Ms. Sunday, then successfully complete Story mode on the hard or greater difficulty setting with Monkey D. Luffy to unlock Tony Tony Chopper.

Play data:
Successfully complete Event Battle on the very hard difficulty setting to view the stats for your battle.

Robin's third costume Japanese version:
At the "Press Start" screen, hold L, then press Down, Right, A, B, A2 to unlock Robin's third costume.

Sanji's fourth costume:
At the "Press Start" screen, hold R, then press Up, X, Down, X, Y, B, Y, X to unlock Sanji's fourth costume.

Sanji's third costume:
At the "Press Start" screen, hold L, then press Up, A, Down, A, B, A, X to unlock Sanji's third costume. In the Japanese version, hold L, then press Up, Down, A, B, A, X at the "Press Start" screen.

Usopp's fourth costume:
At the "Press Start" screen, hold R, then press Right, X, Right, X, A, Y, B, X to unlock Usopp's fourth costume.

Usopp's third costume:
At the "Press Start" screen, hold L, then press Right, A, Right, A, B, A, Y to unlock Usopp's third costume. In the Japanese version, hold L, then press Right2, A, B, A, Y at the "Press Start" screen.