I've heard of the Serious Sam series a little bit before I bought the 2nd game on Xbox a few years ago. I honestly didn't think it was going to be on par with Halo or anything, but I wanted to give it a shot since it has a decent PC fanbase.
I do like the many weapons, goofy enemies, and non-serious tone of the game.
However the shooting is just too mindless and the enemy-count gets way too ridiculous. I actually got to about this battle if I'm not mistaken before I shut the console off and took Serious Sam II out of the tray for the final time.