A woman is seen in her panties, butt cheeks can be seen.

There are sexual references in the film like "sluts" and "dick" but there are no sex scenes in the film

A man's bare butt is seen and it was probed by a device.

Reference to punching someone in the dick. Animal mutilation/dead animals (not too graphic). Guns are used. Spilled blood shown.

An alien is shot, you can see its body and some blood- also not too graphic. A man shoots himself, causing his head to explode and blood splatter everywhere including on someone's face, who stays covered in it for a bit after. Graphic. A hand/arm is shown after being ripped from a person. Graphic. It later shows the person with the missing arm. People are shot and killed, blood splatter shown.

Excessive use of fuck along with shit and many other words.

Teenagers are partying at a cabin, doing all sorts of drugs and drinking beer and alcohol through quite a lot of the beginning of the movie.

Marijuana farm is shown.

If this movie had a rating it would be something like: Rated R: sci-fi violence/gore, language throughout, nudity, drinking, some drug use - all involving teens

Teens in a cabin being attacked by aliens- you do the math.

There are jump scenes.