Bart Simpson creatures

The  are a group of s that were created after, in 2014,  Bart Simpson placed a sandwich that he blew his nose on in a time capsule together with his friend 's lucky rabbit's foot and radioactive ooze came in contact with them. At first a group of rabbits, they later underwent metamorphosis, turning into Bart-like lizards, and some posteriorly evolved wings.

The creatures, who were multiplying out of control and destroying New New York (putting the price of starter condos at 99 quadrillion dollars), had Bart's father 's D.N.A., so went back in time from 3014 to  to kill Homer before they could evolve from him, but instead teamed up with the  and. The moon was also closed for renovations.

Getting rid of the creatures
The team quickly discovered that the D.N.A. in the Bart Simpson creatures had only been half Homer's and that the other half had come from Bart's mother. In order not to kill Homer or Marge, they initially planned to kill the one of the  that had sired the creatures, who they eventually learned was Bart, but instead decided to dig up the time capsule. However, the creatures destroyed the generator that powered the portal that the crew had used to go back in time, causing them to be sucked back into the future before they could do so.

By promising them bars and tormenting them with the holophonor sounds of a, a rainbow, flowers, and a , Bart's sister  rounded up the creatures in Madison Cube Garden, where  locked them, and the Planet Express ship then shot it into  (like they do to each 's  losers, who that year had been the ). The creatures landed on Omicron Persei 8, where they caused more destruction. The was rebuilt and the generator was repaired, allowing the Simpsons to return to the past.

Species information

 * used purple samples of the Bart Simpson creatures' D.N.A..
 * The creatures' black snouts were originally pink.
 * Homer was able to decapitate the creatures with his hands.
 * After being eaten and pooped out by, one of the creatures regenerated from the feces.
 * The creatures can make -like jumps.
 * After being eaten by Lrrr, one of the creatures turned gray.

Production
The were first seen in a preview clip screened at the Simpsons  panel, which was cut from the episode, on 26 July 2014. They were also alluded to in an article published online by ', on 4 September, mentioned in a preview clip released by ', on 6, and seen in a preview clip released by the , on 6 November.

Trivia

 * Among the pre-metamorphosis are  and Bongo from Matt Groening's .
 * Commonly referred to as creatures, the creatures are also referred to as s, killer rabbits, horrific creatures, "", Barts, goblins, Bart's children, and horrible Earth creatures.
 * The creatures' metamorphosis resembles the hatching of from the.
 * Like Bart, the creatures say "" and "", make fun of (by shooting lasers out of their eyes and writing "SKINNER IS A WIENER" on a wall), show their butts, and write "" on walls. Other things done by the creatures include biting Hermes, stealing Planet Express's office supplies (which  considers inexcusable, even though he stole some too), eating, shutting down one of the Channel √2 News cameras, attacking the population, removing Scruffy's mustache (which leads to him shooting himself), eating rocks, and biting Nibbler.
 * The creatures reappear in Simpsons Comics Treehouse of Horror #21.