Recognizable creatures of the Known Atmos
Bog Howler: Large ape-like creature with red eyes, grey-brown skin, swamp green fur, long pointed ears, thin curved horns, and an upturned nose. Bog Howlers are known to inhabit Terra Greusomis.
Cat: Similar in appearance to Leapers but twice as large and more cat-like behaviour.
Chicken: Come in many colours as well as giant versions.
Cloud Krill: Small harmless, and delicious, creatures that swim the cloud-seas in massive swarms
Dragon: Thought to be extinct Dragons were once the most common airborne creature in the Atmos, they were hunted down when the people of Atmos took to the sky and saw them as a threat. The Dragons fought back in self defence but to no avail and were driven to the brink of extinction. A large clutch of Dragon hatchlings have been discovered recently and with the protection of Rinjiin, the last of the Dragon Knights, and the other Sky Knights of Atmos the baby dragons will reach maturity in 60 years.
Elephant Ant: Insect of unknown description inhabiting the Wastelands.
Enormous Meat eating Plant: Native to the Black Gorge that lives in the area called Meat-trap Marsh.
Fire Scorpion: A giant scorpion that is native to the Wastelands. The creature can shoot fireballs out of the tip of its tail.
Giant Eel: Native to the Black Gorge.
Gleep: Timid blue lizard like animal that lives on Terra Wallop.
Leaper: Strange animal that lives in dry, arid, desert-like climates. Tan coloured with tall pointed ears and no discernable limbs.
Leviathan: Giant pest of the cloud-seas that feeds on cloud krill and the occasional fishing ship by disguising itself as a terra. The Leviathan can be repelled by the signature extra potent quadruple malt vinegar sold at the Sky Side Shanty.
Living Tar: Native to the Black Gorge.
Magma Beast: Native of the Wastelands, large snake like creature that lives within the lava pools and is agressive towards anything that happens by.
Merbian Carrier Pigeon: Small grey bird with a thick finch-like beak used to carry messages
Minnows: Common small fish of Atmos.
Mud Eel: Inch long creature that nibbles moss. Mud eels are found on Terra Aquinos.
Mynall Bird: A colourful hawkish bird of unknown origin.
Pandaseal: Animal of unknown description - mentioned in the episode 'Second Chances'
Phoenix: Very large birds completely engulfed in flames. These birds are very territorial and protective of their nests and the Phoenix Crystal with which they are linked.
Poison toothed Spiny Gorge Sloth: Native to the Black Gorge. Appear as bipedal prairie dog-like creatures until exposed to sunlight where they then become large, dark and dangerous.
Scarlet Maw Tickle Fang Arachnoid: A spider similar in appearance to the Scarlet Maw Razor Fang Arachnoid but completely harmless whereas the other is one of the most dangerous creatures in the Atmos.
Scorpion fly: Insect of unknown description inhabiting the Wastelands.
Skoat: A herd animal of unknown description.
Sky Monkey: Highly intelligent and perceptive creatures that resemble rabbit/lemurs.
Sky Rodent: Cat sized mouse-like creature that enjoys living in garbage.
Sky Shark: Aggressive and dangerous creatures that endlessly patrol the skies for cloud krill or other food.
Sky Squid: AKA sky squidees a food favoured by Wallops. They are a brown-orange with four tenticles and lighter spots.
Sky Worm: Possibly akin to a Sky Monkey in that they are also highly intelligent and perceptive. The giant worms are flat, flesh toned with a single large eye and possess thin forearms (Seen only once in the episode 'Sky's End')
Verroc: Large cat-like bats that inhabit the underground of Terra Vapos.
Venomous Cricket: Insect of unknown description. Highly dangerous.
Vulca Bat: Native to the Black Gorge that feeds on metal.
Credits
Information references include Wikipedia, the stormhawks website
and personal observation.