So far, of all the Build engine games I've bought from GOG, BLOOD delivers one hell of an experience. It's not got the "immersive" environment and deep story and characters from some modern games, however, this game is not about story, it's about having a hell of a lot of fun lobbing dynamite at cultists and hearing an ear piercing (and somewhat hilarious) AAAAAAAARRRRRRGGGGGHHHHH.
BLOOD boasts some serious firepower. You play Caleb, a professional 1800s Edwardian era gunslinger with some serious issues. Caleb wields a pitchfork, flare pistols, sawed off shotguns, Thompson machine guns, Napalm launchers (which will really give off a serious bang) various forms of dynamite, Tesla cannons and more.
Join Caleb as he destroys anything in his path to redemption. Again this game is about destroying anything that moves, and it's actually quite a big one at that. Four awesome episodes (it includes the Plasma Pack) and lots of guns, enemies and blood means there's lots of fun to be had.