Sixteen-year-old Barney is resigned to another boring vacation at his parents' summer rental, reading science fiction novels and keeping out of the sun. When Zena, Manny, and Joe move into the cinder-block cottage next door, Barney is intrigued by their glamorous, exotic lifestyle. His fascination grows when Zena introduces Barney to their favorite pastime: Interstellar Pig, a board game in which the key objective is to finish the game with the Piggy card in hand.
Zena quickly briefs him on the rules: each player picks their character from a box of cards depicting different aliens. Every alien race has their own strengths, weaknesses, and IRSC (Interstellar Relative Sapience Code, which rates the species' intelligence). When the time runs out, every home planet will be obliterated except the one belonging to the holder of the Piggy.
Soon Barney is immersed in the game. But why do his neighbors keep picking the same aliens every time they play, and dissuade him from learning about themselves? Is it just a game? Or could the fate of the entire planet be at stake?
It was followed up in 2002 by a sequel, Parasite Pig, where Barney is once more pulled back into the game.
This novel contains examples of:
- Absurdly High-Stakes Game: Specifically, the fate of the players' world, which is the only one to survive when the game ends - all other planets in the game are destroyed. Supposedly, at least.
- Ambiguous Ending: While holding onto the titular Pig, it tells Barney that the whole "Only the species that holds me is safe" is a lie that it had spread because it wanted to see other worlds. Whether or not this is true is left unanswered.
- And You Thought It Was a Game: The actual board game is described as a "simulacrum" in order to dissuade non-participants from keeping the Piggy and therefore getting pulled into the real game themselves.
- Cannot Tell a Lie: The lichen are capable of transmitting information amongst themselves, but they are incapable of transmitting false information, or lying, to others. Barney takes advantage of this, while disguised as a lichen, to get more information.
- Chekhov's Gun: The equipment Barney selects, and the Captain's diary.
- Chekhov's Gunman: Luap, though posthumously, and the lichen.
- Determinator: Despite having a horrible sunburn, and the fact that it would be a rather long trip across the ocean, Barney still manages to convince the others to take him along to the island, and as a result, manages to get to the Piggy first.
- Fish People: Jrlb is a walking fishman.
- Giant Spider: Zulma is a giant, alien spider.
- Hidden in Plain Sight: Barney cuts a hole in the pages of an old yearbook, hides the Piggy inside, then leaves the book in plain sight on a bookcase.
- Hive Mind: The lichen think and act as one.
- Humans Are Morons: When Barney is pulled into the game, his IRSC is listed as 93.7, which, by the games rules, only puts them above the Lichen in terms of relative sapience. Inverted, however, when Barney becomes the only one who realizes what the true purpose of the game is.
- Hyperactive Metabolism/Wizard Needs Food Badly: The carnivorous lichen can eat nearly anything and have to because of their hunger cycle being constant.
- Living Gasbag: Moyna, a gas-filled flying octopus.
- Needle in a Stack of Needles: Barney manages to hide from Moyna in the swarm of lichen by using his Disguise Selector to turn into one of them.
- No Good Deed Goes Unpunished: At the end of the book, Barney decides to help Moyna get to her craft because she's running low on the gas keeping her aloft. This merits him a (non-serious) gash on the arm as "reward".
- Posthumous Character: Luap.
- Starfish Aliens: Zulma and Moyna; Jrlb is humanoid.
- Timed Mission: The Board Game Interstellar Pig is timed. No one knows how long the Real Life Interstellar Pig goes on, because this is still the first game.
- Uncanny Valley: In-universe; the Piggy, its smile in particular, severely creeps Barney out.
The sequel contains examples of:
- Back for the Dead: Moyna and Zulma are both killed off by the time the story is over.
- Impaled with Extreme Prejudice: Zulma gets shot with a crossbow, which goes all the way through her. Moyna suffers the same fate before being devoured by the lichen.
- Uncertain Doom: Jrlb, who was last seen being attacked by the carnivorous lichen and ducking underwater, which may or may not have saved his life.