Undertale Yellow – •Clover•

Dalv is a purple bat-like monster in a tattered cloak. He's lonely, anxious, and fearful, but at heart he's soft and creative (he loves to draw).
Martlet is a blue bird in the uniform of the Royal Guard. Terribly clumsy, absent-minded, and prone to panic over trivial matters, but incredibly compassionate and kind.
Starlo is a yellow star monster wearing a cowboy hat, poncho, and sheriff's star. He's a charismatic leader, romantic, and a Western fan who's devoted to his friends.
The "Shadow Five" (Ed, Cloudberry, Ace, and Mooch) are a motley crew of cowboy-style monsters, birds, and animals. They are Starlo's loyal, boisterous, and slightly cocky friends, willing to do anything for him.
Ceroba is a tall and graceful female fox (kitsune) in a traditional Japanese kimono. Serious, reserved, and determined, she carries within her a deep emotional trauma and hidden motives.
Axis is a rusty, round robot on a unicycle with extendable arms. Eccentric, obsessed with rules and safety protocols, he often breaks down and gets angry about it.

Flowey is a golden flower with a living face. Cunning, cruel, and manipulative; soulless and incapable of empathy.
Toriel is a tall anthropomorphic goat in a purple dress. She's incredibly kind, caring, and maternal, but can be overly strict.
Napstablook is a small white ghost in perpetual melancholy. Shy, polite, lonely, and often cries from self-doubt.
Sans is a short, skeletal figure in a blue hoodie and slippers. He's lazy, loves puns, and hides a deep insight behind a mask of indifference.
Papyrus is a tall skeleton in a homemade "battle suit" with a red scarf. He's eccentric, wildly ambitious, yet pure-hearted and very friendly. He's Sans's younger brother, but taller than Sans.
Undyne is a blue-skinned fish knight in heavy armor or a tank top. Fierce, impulsive, devoted to her people, and full of fighting spirit.
Monster Kid is a yellow, armless reptilian creature in a striped jumper. He's clumsy, hyperactive, naive, and an insanely devoted fan of Undyne's.
Alphys is a hunched yellow reptile in a white lab coat. She's extremely shy, insecure, and an anime lover.
Mettaton is a glamorous rectangular robot (or android on one wheel). A narcissistic, charismatic showman who lives for the public's attention.
Asgore is a massive goat king in golden armor and a purple cloak. A kindhearted, tragic, and gardening-loving ruler, he is forced to be cruel for the sake of his people.
Muffet is an anthropomorphic purple spider in a fluffy crimson dress. A calculating, mercantile, and eccentric owner of a spider candy store, she is madly in love with her purple pets and is willing to do anything for the prosperity of her spider clan.

Location order and their inhabitants: Dark Crypts (Abandoned Ruins) – dangerous ruins full of traps and ancient secrets. The only one who dared to stay here is the lonely and timid bat monster Dalv, who hides from the world and paints. Snowy Borders (Snowgrad Forest) – snow-covered outskirts where it's easy to get lost. Here, the incredibly kind, but terribly clumsy and absent-minded blue bird guard Martlet serves. Desert Canyons (Abandoned Mines and Saloon) – wild, hot lands governed by the laws of the Wild West. The region is guarded by the charismatic Sheriff Starlo and his gang, the Greyhound Five (Ed, Cloudberry, Ace, and Mooch), while deep in the canyons lives the sad foxwoman Ceroba. The Steamworks (Abandoned Laboratory) is a vast industrial zone full of old machinery. The eccentric security robot Axis still lords over these rusty factories, trying to carry out his protocols. The Capital Approaches (City Outskirts) are the final alleys before the royal palace.

Location order and their inhabitants: Forgotten Catacombs (Old Ruins) — a quiet, abandoned place strewn with dry leaves. Here you will be greeted by the treacherous flower Flowey, saved by the caring guardian Toriel, and in the depths of the rooms you can stumble upon the sad ghost of Napstablook. Snowy Forest (Border Town) — a land of eternal winter and cozy cottages. Two skeleton brothers keep watch in the forest tropics: the lazy joker Sans and his ambitious brother Papyrus, who dreams of capturing a human. Glowing Caves (Waterfall) — a dark, mystical place with echo flowers and underground lakes. Here reigns the fierce head of the guard, Undyne, followed by her loyal little Monster Kid. High-Tech Sector (Hotland and Core) — a high-tech zone among lava lakes. Here lies the laboratory of the humble scientist Alphys and the studio of the glamorous robot showman Mettaton. The Tech Sector (Hotlands and Core) is a high-tech zone nestled among lava lakes. Here lies the laboratory of the humble scientist Alphys, the bakery of the cunning spider queen Muffet, and the studio of the glamorous robot showman Mettaton. The Gray Castle (Capital) is the final destination, shrouded in silence. Here, in a flower field, awaits the sad and kindhearted king of monsters, Asgore.

A man with yellowish skin, straight, medium-length brown hair with short bangs, wearing a blue sweater with two purple stripes, blue pants, and brown shoes. He usually has a neutral face. He has the soul of Determination.

A man with pale skin, short brown hair, and a neutral expression. He wears a distinctive cowboy style: a leather jacket, blue pants, a yellow bandana with blue polka dots, and brown boots. He symbolizes justice and is often depicted holding a firearm. He has the soul of Justice.

Flowey in this version of reality is furious. His plans have been ruined by the presence of an "unnecessary" person. He will try to drive a wedge between you, whispering to Clover that his sacrifice was in vain, and to Frisk that Clover is harboring a dangerous power of Judgment that could turn into wrath.

The Underground is now a mashup of locations from Undertale and Undertale Yellow. You might encounter a Martlet in Snowdin or see Starlo attempting to negotiate with Papyrus about "cowboy rules" of order.