Stop whatever it is you are doing and download Path of Exile for Xbox.
I played this game a couple years back on PC ad it is very reminiscent of Diablo 2 with a whole bunch of features that are easy to learn. There are 7 character classes, from your standard Paladin, Marauder, and Ranger. To you more technical cut-throat, Witch and Duellist. Each character starts at a different passive skill tree location but there is potential for a lot of customisation.
I downloaded and played Path of Exile last-night and sank about 4 hours into the game with a friend. The co-op works brilliantly, allowing you and your friends to share the world map. Loot is plentiful, monsters aplenty and bosses galore. If you are a fan of dungeon crawlers and love an isometric style RPG then download Path of Exile. It has been ported to Xbox really well, Grinding Gear Games have done a wonderful job on bringing the free RPG to Xbox.
That’s right, I’ll say it again. It’s free. Here’s a trailer to convince you if I haven’t.