It is a camp fest, and a satire of the SF horror genre, but if it has any deeper meaning, it is as a paean to schlock SF movies and the way a young person could use them to explore the unknown land of sexuality and identity.
The main no-no is wearing a striped top. Apparently members of the crew were accidentally caught on screen wearing striped sweatshirts during the filming of the 1975 The Horror Picture Show* and stripes have been frowned upon ever since.
Free-for-All, also known as "FFA" or "Deathmatch" in Call of Duty and Call of Duty 2 as well as "Wolfpack of 1" as an April Fool's day joke, is a multiplayer mode featured in every main Call of Duty game, which puts every player against each other.