The overall graphics and game play are just above average. The story line is very interesting and gives you the full zombie experience.
Although the puzzles can get very easy at times, they are still very challenging and often require lots of thought. It's a perfect mix of puzzle and shooting. The goal is to stay alive as long as possible, while doing so you must collect as much ammo, health, or money as possible. There are two things that happen in this levels - you have to fight your way through and protect yourself from the infected enemies and the endless waves of the zombies. The game starts out with Serious Sam (as he was known in the first game), who has somehow landed in the underground facility. If you love shooting games with a ridiculous premise, than Serious Sam is for you.
It's a little old-fashioned, but it still pulls it off with flying colors. You basically have to obtain weapons, armor, health, and ultimately extra lives by beating enemy waves. A crazy, funny, and absolutely crazy game.