How to make real-time shadows like in Dungeon Hunter 4 on mobile platforms?

I found that Dungeon Hunter 4 has very $$anonymous$$gh quality real-time shadows for all characters in scene, and even self shadowing could be found on the avatar if you zoom the camera in. The shadows in Dungeon Hunter 4 are very clear and $$anonymous$$gh performance. Does anyone know what technique and optimization trick do they use to implement t$$anonymous$$s?