There is a fairly lengthy campaign, an online competitive mode, puzzle challenges, and a verses option. (darkstation.com)
If you're not looking to play a lot of multiplayer matches I would recommend renting though because it is not a very lengthy campaign. (andymerrill.com)
The only problem is that you have to play through the same lengthy campaign to build up a new character if you want to fully play around with them. (mic.com)