- Main article: Jabberjay
The jabberjay is a type of bird that was created to spy on enemies of the Capitol. Jabberjays had the ability to memorize and repeat whole human conversations, and were used to eavesdrop on the rebels. Once the people in the districts realized how their private conversations were being transmitted, they used the jabberjays to feed lies to the Capitol. The Capitol therefore ceased using the jabberjays and abandoned them to die off in the wild.
But to the humiliation of the Capitol, the solely male Jabberjays unexpectedly mated with female mockingbirds to produce the mockingjay. However, by the 75th Hunger Games, the Capitol had replenished the jabberjay population and used them in one of the time "sectors," where tributes Finnick Odair and Katniss Everdeen were trapped and forced to listen to the birds' mimicry of their loved ones' screams. They were described as black and crested, similar to the mockingjays' appearance.
- Main article: Mockingjay (bird)
Mockingjays are accidental muttations that were created when female mockingbirds mated with male jabberjays. They pick up songs very quickly by imitating the pitch of a human's voice and can relay them back and forth to people or other mockingjays. Since the Capitol did not mean for these birds to exist, they are viewed as a symbol of rebellion within the districts. However, after victor Katniss Everdeen's use of a mockingjay pin in the Games, mockingjays went into vogue with the people of the Capitol and their likeness often appeared in clothing, jewelery, and other objects. The Mockingjay pin is a symbol of rebellion, since Katniss wore it in the Hunger Games. Mockingjays are mainly black like the father Jabberjays, with white patches under their wings from their mockingbird parents. They have a crest, also inherited from the Jabberjays, which may be similar to that of a bluejay.
- Main article: Tracker jacker
Tracker jackers are deadly wasps that were made by the Capitol and placed around the districts during the first rebellion. They are larger than regular wasps and have a gold-colored body. Their stings raise lumps the size of plums on their victims, and their venom (engineered to target fear in a victim's brain and alter their memories) causes hallucinations that can drive people to madness. More than a few stings will kill a person; some people die after just one. These mutts will also hunt down anyone who disturbs their nest and attempt to kill them, hence the name tracker jackers. They live in huge hives high up in trees.
In the 74th Hunger Games, the Gamemakers released a pack of wolf-like creatures on the final three tributes, Katniss Everdeen, Peeta Mellark, and Cato. These creatures were able to balance on their hind legs and jump very high, and had four-inch long razor-sharp claws. Each of the mutts resembled one of the tributes who had died previously in the Games, had a collar marked with the district number of the tribute it was based on, and had eyes that looked remarkably human. This was achieved by using Capitol technology to recreate the humans, mixed with a form of wolf. This made them look so much like their Tribute, that Katniss wondered if they had been made using the tributes' real eyes. The muttations mortally wounded Cato trying to kill him but he was armored with some Capitol-created armour. Katniss and Peeta listened to him suffer for the night before she was able to take a mercy shot and put him out of his misery. The 74th Hunger Games was the only known year that these creatures were used, acting as a painful and effective weapon to drive together the remaining tributes at the Cornucopia. Katniss recognized five wolf mutts: Glimmer, Foxface, the boy from District 9, Thresh and Rue. Katniss realized what these muttations were when she shot the wolf mutt that was Glimmer.
In the film, the mutts don't resemble the tributes at all. They look more like large, vicious, bulky dogs. They run on all fours, and resemble each other. In the book they could balanced on their hind legs and jump high, but in the film they did not. The wolf muttations had brown, grey, black, or silver fur, and short muzzles. The Gamemakers designed these beasts in the "Control Room", where they monitor everything that goes on in the games. We first see these mutts when a Gamemaker shows a hologram of one to Seneca Crane for evaluation. He says that they're excellent, so the Gamemaker inserts it into the Games. In the film, the mutts are responsible for the deaths of Cato and Thresh. At the end of the scene, the muttations run off into the woods, instead of jumping into a tube which leads back to the Capitol like in the book. Also in the film, Katniss gives Cato a mercy shot much more quickly.
In the 75th Hunger Games, the third Quarter Quell, one section of the arena, which was a clock, contained a mutated species of an orange colored monkey that viciously attacked the tributes, harming them and even killing the female Morphling when she saved Peeta's life. They used their claws and their teeth to make deep punctures in their victims' flesh that looked harmless, but in reality were deep enough to cause internal bleeding. The group left the beach after the morphling died so the hovercraft could take her body away. According to Katniss, their claws come out like switchblades and they are very agile.
In Mockingjay, after President Snow realizes that he did not manage to kill Squad 451 and that they escaped underground, he sends lizard-like muttations after them. The mutts were four-legged with sharp talons at the end of each finger, had tight pale white skin and were the size of humans. On their hind legs, they had long reptilian tails, arched backs and heads that jut jaws which enabled them to decapitate their victims in one bite. The mutts had the ability to walk on their hind legs as well as on all four, which Katniss described as skittering movements. When Katniss got closer to them, she saw that they seemed to be a mixture of humans and reptiles, with faces of conflicting features. They gave off a scent similar to that of President Snow's roses and had Katniss' scent to track her. They spoke through mostly hisses but were also given the ability to say "Katniss", most likely to frighten her. They were able to be killed but only were killed when Katniss detonated her Holo on them (by saying "nightlock" three times), though they managed to kill most of Squad 451—Jackson, Leeg 1, Finnick, Castor and Homes—before their annihilation.
- In the 75th Hunger Games, one of the time "sectors" in the arena had an unidentified mutt in it which ripped apart a tribute so badly they could not be identified. That Mutt was labeled as extremely large and very fast. It was known as the Beast.
- Another section contained a large quantity of insect-like creatures, much like grasshoppers or crickets, but with large pincers that they would click continuously. They were a serious threat when they swarmed, which caused tributes to attempt to avoid them at any cost.
- It was said that in the 50th Hunger Games (2nd Quarter Quell) there were golden, fluffy carnivorous squirrels, stinging butterflies, and candy pink birds, that killed Maysilee Donner.
- Muttation gnats and flesh-eating rats were mentioned to be in one of the pods found in the Capitol during the attack by the rebels.