We very briefly thought Namco was making a One Piece/Thundercats crossover game, only to realize that the company just announced release dates for two separate games in the same press release for some reason.

One Piece: Pirate Warriors, the downloadable PS3 game (which is already an unlikely crossover of sorts, being a One Piece-themed action game in the style of Dynasty Warriors) will be released in North America on September 25.

Also coming September 25: the side-scrolling DS Thundercats game based on the new cartoon, which casts the player as Lion-O. So that's One Piece: Pirate Warriors and Thundercats - but not One Piece: Pirate Warriors and Thundercats.