Omega Force added Haki to One Piece: Pirate Warriors 2. Luffy’s Haki can knock out a bunch of units nearby using Conqueror’s Haki. Zoro’s Armament Haki buffs his attacks. Eneru has Observation Haki that makes attacks chain into combos.
One Piece: Pirate Warriors 2 also has a Style Change system. Attacker type style change gives characters like Luffy and Sanji a huge attack boost. The technical type style change speeds your character up and gives you the feeling that everyone else is moving really slow. You can activate a Style Change by pressing R1.
Pirates Log is a new mode that has an original story with a three way struggle between the Marines, Pirates, and the Straw Hat Crew.
One Piece: Pirate Warriors 2 comes out for PlayStation Vita and PlayStation 3 on March 20 in Japan. Namco Bandai has a North American and European release slated for summer 2013.