Marvel Super Hero Squad Online is a f2p Browser MMO for Windows and Mac that uses the Unity Engine. The game is geared towards kids but as an adult I’m enjoying the simplicity but fun gameplay of it. There are a variety of missions to choose from in which you can level up your heroes. There are lots of heroes of choose from though a lot of them you have to buy with gold which doesn’t come quickly unless you pay for the subscription services or buy the gold directly. I’ve only been playing a few days and I already have around seven heroes and I play casually so it is good enough for me. Check out the video for an idea on how it plays!
The Gameplay starts 1 minute in.