Like the first Diablo? Alien Shooter 2: Reloaded, here on GOG.
Checked out the page, looks really awesome.
It's awesome. :D
I chose it as prize from a giveaway hosted by Detlik (thanks again, mate!), during the Xmas sales, and it was a very good choice. :)
While I was playing it, it continuously reminded me of the first Diablo (including the huge hordes of enemies). It's a mindless, amazing slaughter of aliens monsters, a hell of a fun. I didn't stopped until I end it (both the main game and one of the really hard alternative modes, the other two were just impossible).
BTW, I wish for the Zombie Shooter series to finally arrive to GOG. The gameplay of Alien Shooter 2 plus the Zombies background (I'm a great fan of the genre) is a sweet combination that I'm looking forward to play. :)