This is one of those movies that has everything going for it except for a few problems in the writing. The performances are good, it's well-shot and edited, the cast and crew seemed to be having fun (bloopers are scattered throughout the end credits), there are impressive practical FX, the music compliments the visuals, and there are a few creepy moments.
On the writing end, issues begin with the characters, who are one-dimensional. There's a cop who's only there to spout exposition, the mean fat guy and the loser whom he bullies, the psycho war veteran, the token black guy, a bland redneck, and a blander final boy. This is a low-budget horror movie, and I can forgive the character shortcomings, so let's move on... It wants to be a comedy, but it's really not that funny, and the pacing is off. There's one particular scene that only exists to make viewers squirm - they try to frame it in a supernatural way, but it doesn't work and feels like it belongs in a Jack Black movie or something. But my biggest problem is with the twist, which I won't spoil because it comes totally out of the blue. After the credits rolled, I immediately started the movie over, expecting to find some foreshadowing that I'd missed, but it just ain't there. I did enjoy the movie more the second time, though.
Deer Camp '86 works as a throwback (although it feels more early-'90s than mid-'80s), and it's definitely better than the crap mainstream Hollywood has been churning out lately, but it's neither the masterpiece nor the disaster that other reviewers have claimed. I'd imagine it works best with an audience and intoxicants.