If you are specifically looking for high-quality beat-'em-ups that actually run on the PSP, consider these titles available at retailers like Amazon or eBay:

: This is currently the most popular way to play the game on the go. You can find it on the Nintendo eShop.

: While for the successor to the PSP, it captures the same colorful, chaotic energy of Castle Crashers .

: A gritty, high-quality brawler based on the classic film.

: Many sites use popular keywords to lure users into downloading malicious software. Verified ISOs only exist for games that were actually manufactured for the console.