Basic plot: Jason's back, and he likey killy. You, as a band of six camp counselors, must protect yourself as well as the kids from his murderous wrath using a phatty-boom-batty sack of god damn rocks.
I'm not even kidding you. You can't make this shit up. You and your friends are armed, at the start, with a bunch of rocks. Actually, according to the instruction manual, they're sharp rocks. Well, that makes all the difference then, doesn't it? I'm sure that tossing a rock at Jason's decomposing skull will convince him to just turn tail and run like a little bitch.
But I digress. When the game begins, it's daytime. It'll stay that way for about six or seven minutes, and then dusk will come, night will fall, and you'll realize that you're going to spend the entire night tossing hunks of stone at an invincible serial killer.
You see, on your map screen, you can get a vague idea of the layout of the camp.
You heard me. ZOMBIES. Apparently, Jason's not the only card-carrying member of the undead on the grounds. Along the paths, zombies will continually sprout from the ground. And they'll do it in the woods. And in the caves. And when you're rowing across the lake, yup, they'll lunge out of the water like a gaggle of low-rent creatures from the black lagoon. This, along with overly hostile local wildlife (dogs, birds, etc)
Now, let's say you make it to Jason. Don't worry, you'll get the hang of charging through the paths soon enough. Hopefully, somewhere along the path, you found a knife or maybe even a machete, so that you can stand a chance in this battle. Once you're there, you'll find that, for the first fight, he's gonna use his fists. No problem, you think. His fists vs. my knife equals Jason sushi, right? Wrong, jackass. This is the guy who decapitated a man with one blow in Friday the 13th Part VIII: Jason Takes Manhattan. Four punches from the J-man and you're down on the ground like a limp sack of "sharp rocks." You think that's fun, just wait until he gets his axe. Or his machete. By then, you'd better hope that you've either gotten the torch (Jason hates fire) or the pitchfork (yes, this is the ultimate weapon) to deal with him. Otherwise, it's two hits from his arsenal to send you to that big beautiful summer camp in the sky.
Sensing a trend? The point of all this is that you're gonna fucking die. Fighting Jason is death. Getting to his location in time to fight him is probably death. Battling the disembodied ghost head of Pamela Voorhees (which you must do repeatedly in order to obtain many of the game's best items) is death. Facing the unimaginable hordes of beasts that inhabit the woods is, yup, death. This game will kick your ass six ways to Sunday. Only with great practice, expert timing, and a few hours of your all-too-brief life will you be able to defeat the beast. Or maybe with a Game Genie. That works too.
And if you do, what then? What if, after three days (game time) of this nonsense, with Jason getting stronger and faster with each day, you actually take him down with your pitchfork? Why, then you get a single screen where Jason slouches in the corner and you're told that you won, maybe. Awww, see, the widdle guy's all tuckered out! Time for your nappy-poo, Jasey.
Only the most passionate of F13 fans need apply. For the rest of you, stay far, far away.