The Atomic Critter
Universe
Welcome to the Atomic Critter Universe, where questionable science, emotional damage, and mutated animals collide. This page connects the characters, lore, and apparel that make Atomic Critter Clothing more than just merch — it’s a world you can wear.
The Atomic Heart Engine
Engine? | Reactor? | Machine?A sentient energy system buried beneath Sunrise Sanctuary, the Atomic Heart Engine amplifies emotional resonance and reshapes all life it touches.
Buried deep beneath Sunrise Sanctuary, the Atomic Heart Engine was not a machine in the traditional sense, but a living system that listened as much as it consumed. It drew power from emotional resonance—fear, devotion, resentment, love—measuring what was offered and deciding what to return.
When awakened, the Engine did not choose heroes or villains. It amplified what already existed, reshaping bodies and fates according to what each heart carried into the chamber below.
Belli Badger
Who? | Clearly a Badger.. right?An unstoppable force of optimism and strength, Belli Badger emerged from mutation as a living embodiment of atomic momentum and morale.
Nothing to see here. Or is there? I mean, there are a whole bunch of shirts and stuff in the shop for this badger.
Cheeseball
Fennec Fox | Metal GodA sonic-powered engineer mutated by the Atomic Heart Engine, Cheeseball rebuilds what chaos destroys using sound, ingenuity, and raw creativity.
Cheeseball — Original
Creative, curious, and endlessly tinkering, Cheeseball had a knack for taking broken things apart—and occasionally putting them back together.
Cheeseball — Post-Mutation
After the Engine’s detonation, sound became her medium. Cheeseball channels sonic force to build, repair, and sometimes weaponize innovation, becoming both engineer and savior in the chaos that followed.
Coop | Cooposaurus Rex
Part Dog | Part Trash Panda | Part KaijuA colossal mutation of pure loyalty and mass, Cooposaurus Rex is the amplified form of Coop’s affection, transformed into overwhelming force.
Coop — Original
Big-hearted, affectionate, and completely unaware of his own size, Coop was the emotional anchor of the Sanctuary. His love arrived fast, heavy, and usually involved knocking something over.
Cooposaurus Rex
The Engine amplified what was already there—turning warmth into force and loyalty into mass. Cooposaurus Rex is colossal, chaotic, and devastatingly affectionate, still trying to cuddle in a body built like a disaster.
Fin | Fin Night Grelim | Fin-O-Tron
Android DogSmall but fearless, Fin is the emotional heart of the Sanctuary, whose mutation and mechanical rebirth forged him into something resilient and brave.
Fin — Original
Small, gentle, and endlessly brave, Fin was never meant to be a hero. He hovered close to danger not because he was fearless, but because he cared too much to stay away.
Fin — The Night Gremlin
When the Atomic Heart Engine detonated, Fin was caught in its pull—lifted, altered, and broken in the same instant. For a brief moment, he gained wings, only to lose them just as quickly, leaving scars that would define everything that came next.
Fin — Fin-O-Tron (Early)
Rebuilt with Engine shards and sound, Fin-O-Tron is not a weapon, but a survivor. Mechanical and scarred, he carries the weight of what was lost beneath the Sanctuary, hovering forward with courage that refuses to shut down.
Kagen
Grounds KeeperA quiet groundskeeper drawn to the power beneath the Sanctuary, Kagen’s connection to the Atomic Heart Engine reshaped his fate and convictions.
Kagen worked the grounds in silence, overlooked and unpraised, feeding the Sanctuary while something darker grew inside him. Where Renji offered warmth, Kagen carried resentment—and the Engine noticed.
Drawn to the power beneath the Sanctuary, Kagen became entangled with the Atomic Heart Engine, walking away from the blast altered and convinced he had been chosen, leaving Fin behind in the shadows below.
???
Easter EggWho is this guy? A new character not introduced yet? Just a random overly protective dog-mastodon critter? Will we ever know???
Only time will tell.
For now -
This feels like a MIGHTY moment.
Use code MIGHTY at checkout for 20% off orders over $50.
One use per customer. Can’t be combined with other offers. Excludes shipping.
Ends soon.
Murder Otter
River OtterCharming, precise, and terrifyingly efficient, Murder Otter is a post-mutation predator whose intelligence became lethally focused.
Murder Otter — Original
Charming, playful, and unsettlingly intelligent, Murder Otter always seemed one step ahead—watching, learning, calculating.
Murder Otter — Post-Mutation
The mutation sharpened what was already dangerous. Fast, precise, and smiling the entire time, Murder Otter moves through the Sanctuary like a velvet missile, leaving chaos in his wake.
Renji
CaretakerThe compassionate caretaker of Sunrise Sanctuary, Renji represents the human heart of the refuge built above the Atomic Heart Engine.
Renji was the heart of Sunrise Sanctuary—a caretaker guided by patience, routine, and deep affection for its residents. He believed that care, consistency, and kindness were enough to keep darkness at bay.
When the Engine awakened beneath the Sanctuary, Renji paid the price for standing too close to its truth, left injured and unaware as the world around him changed.
Slug Cat
Part Cat | Part Slug… Maybe all cat actually.A gravity-defying enigma, Slug Cat floats through the Atomic Critter universe glowing with residual energy and silent judgment.
Slug Cat — Original
Slow-moving and quietly observant, Slug Cat drifted through the Sanctuary with an uncanny awareness, always watching, always judging.
Slug Cat — Post-Mutation
After the Engine’s release, gravity no longer held the same authority. Slug Cat now floats just above the ground, glowing faintly, powered by atomic energy and pure indifference to everyone else’s problems.
Sunrise Sanctuary
Where it all beginsA peaceful animal refuge unknowingly built atop the Atomic Heart Engine, Sunrise Sanctuary became the origin point of every mutation that followed.
A quiet refuge tucked away from the world, Sunrise Sanctuary was meant to be a place of healing—for animals, for people, for broken things. Beneath its wooden walkways and gentle routines, something ancient and dangerous slept.
The Sanctuary became the cradle of everything that followed, unknowingly built atop the Atomic Heart Engine. What was meant to protect life instead reshaped it forever.