Try this game, Guardian Heroes for Windows Phone Devices. This is an addictive game which already enjoys good reviews and rating.
Graphics looks very good and best part of this game is that it is free!!!
Guardian Heroes Details:
Advance Guardian Heroes is a side-scrolling beat ’em up in which the playable characters can perform physical and magic attacks. Physical moves include countering and mid-air dashes. Magic attacks, which drain the MP meter, include element spells and protective barriers. It’s also possible to go into “Hyper Mode”, a faster, more powerful version of the playable character.