One Piece Gigant Battle! , a fighting (and has a little bit RPG element) game developed by Ganbarion and published by Bandai Namco Games
This game has 2 Main modes to play with, one is the Pirate grand prix, generally known as Story mode. The other one is Thousand Arena, generally known as versus mode. The Thousand Arena mode branches into four sub modes, that is the Battle Royale, 1-on-1 Battle, Free Battle, and 100 chain Battle. I’ll only explain the 100 Chain Battle, it is a Survival Mode by pitting you against 100 opponents (one at a time) and you must defeat them all without regenerating your HP in order to be successful.
The Pirate Grand Prix lets you go to the adventures of the Straw hat Crew on 10 different Islands in the Grand Line. One by one, you unlock Islands mainly by defeating the Island’s boss or some Island may unlock upon meeting certain requirements. Upon clicking the Island, there you will face missions like Knockout the opponent or win a point battle. There also special missions that you need to acquire more items than the opponent or even block their special attacks.
It’s a kind of unbalanced. The fighting part can be tolerable as you can level up your characters. There some missions that are hard to accomplish because the AI has an insignificant advantage. A good example is a Defeat the other 3 characters are way easier than get more Diamonds than your opponent. On your first few hours of gameplay, the game would be definitely easy but starting from Impel Down or Marine Ford, everything gets kind of hard. So you definitely need to get strong as Luffy would do.