If you don't have a physical PS3, you can use the on PC.
To install a downloaded Castle Crashers ROM, your PS3 must be running or PS3HEN . CFW: Best for older "Fat" and some "Slim" models.
Castle Crashers is the ultimate couch co-op experience. Whether you're leveling up your Red Knight to spam lightning or hunting for hidden animal orbs, the PS3 version is a fantastic way to experience the game. By following the right installation steps for your ROM, you'll be crashing castles in no time.