Insaniquarium

Insaniquarium Deluxe is a computer game, created by Flying Bear Entertainment, originally published by Pop Cap Games, later taken up by a number of other publishers and based on Insaniquarium, which is similar, albeit simpler. The basic idea: The player runs an aquarium and collects money from cash-pooping fish while preventing said fish from dying by aliens who randomly invade your tank. There are a number of "pets"; invincible creatures with a variety of functions that can be earned as the player progresses through the many levels in regular mode. In the Virtual Tank, an advanced version of the game, dollars have been replaced with shells, and more features are present: There are a few new pets, fish with different moods, new food items, and fish with special attributes.

Note: The pets' stories can be considered spoilers since they are accessed later in the game.

 * Alien Invasion: Subversion: Aliens often pop into the tank and start destroying or eating the player's fish. They don't seem to be in the mood for conquering.
 * Back from the Dead: The basis of Angie the Angelfish's powers.
 * Big Bad:
 * Bread, Eggs, Breaded Eggs: Stanley, one of the bonus pets, is afraid of nothing but badgers, aprons and badgers wearing aprons.
 * Cat Smile: The Star Catcher.
 * Dem Bones: Vert the Skeleton and Bilaterus.
 * Flame War:
 * Game Mod: Different songs, different food colors, and more.
 * Hit Points: The aliens' hit points can be seen when Blip is in the tank.
 * Our Mermaids Are Different: Meryl is a former well-known pop star; when she sings, the fish drop coins.
 * Mook Chivalry/Genre Blindness: Apparently, Ulysses, the type-U alien, can shoot already-lasered energy balls if he wants to, but he doesn't due to an honor code that all cyclopes share, and he's dumb.
 * Mr. Vice Guy: Stinky the Snail, who picks up falling coins for you, knew early on that he was a miser. Clyde, on the other hand, collects money for his mother's operation.
 * Psychic Powers: Blip opens buying options and reveals when fish are hungry, when aliens are about to attack, and aliens' hit-points.
 * Shout-Out: One species of alien is called 'Balrog', a reference to the J.R.R. Tolkien's evil humanoids from Middle-earth.
 * Another, Sylvester, looks like the Alien from... well... Alien
 * Spiritual Successor: Plants vs. Zombies, which was originally envisioned as a sequel.
 * Stalker with a Crush: PsychoSquid's girlfriend gave him that nickname when, after their break-up, he kept calling her and waiting at her door.
 * Stock Sound Effect: PsychoSquid uses the T.Rex roar from Jurassic Park.
 * Widget Series: Let's just say that there's a reason why it's called Insaniquarium.