Mario Cast
Horror Mario / It's A Me
Fake Form: Looks identical to the original Mario, with no differences, only changing when the casual static starts.
Real Form: Remains the same, but taller, all his teeth become sharp and bloody, his eyes turn black with red irises, and he carries a bloody butcher knife.
Likes: Cooking, burning things, fighting Xeno, hanging out with Horror Peach and Horror Yoshi, and playing Mario Kart with Racist and Satanos.
MX / WAHOO
Fake Form: His appearance is identical to one of the original 2D pixelated Marios, only distinguishable by his blank demeanor and the absence of a mouth.
Real Form: Retains his outfit, but his body is now much wider and almost 5 meters tall, and he now has a mouth and a huge smile all the time.
Likes: Killing Lucas, smoking cilantro, playing cards with Lord X, and messing with everyone else by showing the corpse to the Half of Girlfriend, stomping people like Godzilla
Devil Mario / Anime
Fake Form: None
Real Form: Looks just like Mario, but his gloves are bloody and he carries a katana. His eyes are visible, but the entire area around them is darkened. He's possessed by the Boos, who controlled him to obtain the Super Stars, killing everyone in his path.
Likes: Killing furries, partying with Lord X, imitating Goku with his aura, hanging out with Bad Day
I Hate You / The Bonfire
Original Form: The base form of a Luigi from Super Mario World
Current Form: After surviving falling into lava after being pushed by his brother, all his skin melted, including his organs. Although he no longer has eyes, his sockets still have white irises that mimic them. All his bones turned bright red, and somehow, his clothes remained mostly intact.
Likes: Killing Italians who wear Wearing red, yelling at Somari asking who the hell she's talking to when she breaks the fourth wall, eating burnt food
Turmoil / Tumor
Fake Form: None
Real Form: Similar to a Mario model from Super Mario World. This Mario reportedly ate a mushroom containing Yoshi's code, giving him a taste for eating non-human creatures and Yoshi's tongue. It also took away his sight.
Likes: Eating blue and red shells, eating, playing cards, going to the beach
Dictator / Secret History / Capitalist
Fake Form: None
Real Form: A Mario dressed in a tuxedo, tie, without a hat, and always with a cigar in his hand. He originated from a video titled "Secret History of Super Mario Bros." where Mario secretly took control of Princess Peach, becoming the Dictator of the Mushroom Kingdom, killing, silencing, and enslaving people to maintain power.
Likes: Capitalism, stealing, hunting Fatal and Virtual for stealing his stolen money, smoking cigars with Lord X
Stanley/ Commercial
Fake Form: His appearance resembles a 3D Mario; he presents himself as a TV salesman.
Real Form: His mouth is sewn shut but still opens with skin; his arms seem to have very little bone, as they deform easily; and his eyes are usually darkened. He is supposedly not aggressive like the other Madness characters.
Likes: Messing with YouTube commercials, promoting, playing Smash Bros. with Satanos and Hog.
L Is Real / Michael Phelps
Fake Form: None
Real Form: Originating from the Creepypasta "L Is Real," which theorized that the reason Luigi didn't appear in Mario 64 was because he was trapped at the bottom of the Star Fountain in the castle courtyard for 24 years, he appears to be the same as Luigi, but has spent so much time trapped underwater that his skin has wrinkled, and his hands appear to have stretched out, like If I wanted to reach the surface
Likes: breathing air, talking to Sink, eating sushi, shark fights
Coronation Day / Screamer
Fake Form: 2D Pixel Peach
Real Form: From a ROM hack of "Peach's Coronation Day," Peach got lost in the Mushroom Kingdom forest, where she encountered the demon Satan roaming the woods. He possessed her and killed her Mario. She no longer has legs, her hands have been replaced by roots, she has two wooden horns as a symbol of her possession, and her mouth is toothless and has elongated.
Likes: screaming, hanging out with MX, messing with Lord X, having tea with Luther and the Souls, taking care of plants with Soul Silver
In progress but probably too lazy to finish:
L Is Real
G6, W4R, Y0SH, Omega
Somari
Grand Dad
Mr Virtual
The End
Abandoned
Ultra M
Mr L
Mr. Sys
Lucas
D-Side
GB
Somari
I'm missing some, but I don't remember who.