It's not exactly super hardcore but it has a really addictive drop system that I think most RPG fans will enjoy. It's also REALLY fun if you have a friend and it improved greatly.
I recommend just picking up the second one. The first one is really fun but after playing Borderlands 2 it doesn't feel up to scratch.
Castle Crashers is probably your cheapest option. It has 4 player co-op and has RPG elements such as leveling up and upgrading traits as you level, but I wouldn't really call it an RPG. Still really fun to play with friends though.
The only thing that ticks me off about borderlands is how long the beginning is in both games, and the fact there is a playthrough 2 (and 3) makes the game just that much more boring. Otherwise it is a great game, its not true to the RPG genre though because the game is too linear.
Dungeon Siege 3 maybe. I know its nothing like the original but it can't be too bad. Never been a fan but Fable 3? and perhaps Lord of the rings: war in the north?
dark souls is AMAZING but only if you have the time to get into it and dont play... too casually. if you really consider yourself a gamer, its a great game, although it has coop, its sortof hard to connect to specific people, like getting into a match with a friend, so if you really want a game you can play with friends, its not too good.
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