Actually; a pretty decent "hack and slash" diablo type clone.
This is not the best "RPG" game, and is certainly not ever going to worry the guys at Blizzard, but this is a fun and satisfying combat game in the same vein as Diablo (imo).
The flow of the game seems good, the only criticism being that you rarely find yourself wondering into an area where you get your backside kicked (but this is common in this style of game).
If you are looking for complex stories and character interactivity then this is not the game for you. If you are looking for "click, kill, get loot, sell loot, buy weapons, click, kill, click kill...." then you will like this game (I liked it way more the the average review here). Also at higher levels it is very satisfying to watch monsters that previously caused you problems fly halfway across the screen with but a single blow.
I also got this from the bargain bucket of PC world, and while it was a really difficult game to get working with Vista (read the forums) it is one of the more enjoyable games this year.