Smoke Choked

Yeah, that's literally her name.  Although she looks like a loli, she is the dominant boss of Kuma, hence her uncouth name.  She fights using a trick rope and by jumping all over the place.

By MoloMowChow

A cowardly and weak prince, who debuted in the most recent entry of Power Instinct in 2009.  He fights alongside his horse, his knights, and his servants.  If you manage to knock him down (which is easier said than done), he will temporarily transform into Super Prince, who has greater speed and range with his attacks.

By Ahuron

GAME: ClayFighter 63 1/3 + CF: Sculptor's Cut

BASE: Sumo Santa by Joey Faust

M.U.G.E.N. 1.0 COMPATIBLE: No

By Joey Faust & Basara-kun

This version of Super Mario Maker was given some tweaks to his A.I. and attacks to focus more on projectiles.  This is not necessarily the preferable version of the character, but this is a different version if you are interested.

By DJ HANNIBALROYCE (garjian club mix)

By Kazecat

The old MS Paint styled self-insert of Dippy/Chase.  More of a joke character.

By dippypixel

🗿

An ancient relic of M.U.G.E.N., based on some obscure game

Author unknown

The newest scantily-clad, kissing fetish character out there.

Character owned by Neo-Geno450

Character converted to M.U.G.E.N. by MrPr1993

Adds an additional intro to the Delta Warriors by FourthRhyme, along with a few minor edits to the character.

By Derpy Sponge

Specifically, this is one of the giant Mech Hisuis from Mech Hisui's Arcade Mode ending in Melty Blood: Act Cadenza, after Mech Hisui rebels against Kohaku.  Ironically enough, though, this one fights alongside Kohaku in M.U.G.E.N.

By SUI

An NES version of Meta Knight, playing off of his Smash Bros. moveset, all the way down to the gameplay style.

By Kater/N64Mario

The OS-tan version of Windows 2000, the successor of NT Mama, designed by GUHICO of Stranger Workshop.  As one of the many OS-tans, this version of her was created for Nijikaku.

By woman, edited by LenRyou

The first Melty Blood: Type Lumina character in M.U.G.E.N.!  Time to see how many servants he can destroy!

By Kira5472

A brutal edit of one of the Chinese symbol Nijijura Maids.

By woman, Edits by Soren Kisamora

A character from Dancing Sword, an obscure GBA beat-em up.

By Soren Kisamora

Sort of a bonus game, where you beat up Big Chungus before time runs out.  If time runs out, Big Chungus OHKOs you.

By borderoflife

Bonus characters from Jump Ultra Stars.  Comes in three variations: Komayellow, Komared, and Komagreen.

By Aoi Minazuki

A semi-joke version of E.T. that swings around Elliot Taylor, jumps infinitely using his extending neck from the Atari 2600 game, and spawns random characters from the Atari game.

By Borderoflife

Much like the other Girls' Frontline characters, this is a girl based on a gun.  More specifically, this one is based on the Heckler & Koch HK416.

Also, Girls' Frontline is getting an anime, soon?  That's neat.

By Rognarok

You would think a spelunker would fight with tools, right?  Wrong.  This version of the weakest NES character is a shotoklone with 29 lives.  Every special, grab, and/or hyper costs him a life or more than one life.  He also loses lives by being hit by the opponent, as to be expected.  Not absolutely source accurate, but accurate in the sense that Spelunker perishes from even the slightest things (ghosts, bats, falling from not that high heights) in his source game.

He also has gone on to star in a few ports and remasters of his game, as well as some spinoffs (Spelunker World and its enhanced port, Spelunker Party!), and even an anime OVA (Spelunker is a Teacher).

By the Nijikaku team

Many believe this weird combination of Mickey Mouse and a black octopus originates from Nijikaku, but this thing has more history than you might think.  It actually originates from a logo on the packages of Fukujuseikaho cotton candy from the 60s, and went on to become a somewhat notable meme in Japan.  It wasn't until a Hatena user used this character as their profile picture that it caught the eye of the mysterious Nijikaku team.

Anyways, in M.U.G.E.N., Takobue can teleport with golden circles, fire lightning with the Sorcerer's Hat (the one that Fantasia Mickey uses), and a bunch of attacks involving his tentacles.  Nijikaku is weird.

You should check this thing out, though.  It's actually really cool.

By the Nijikaku team

This is Winnie the Pooh at full power.  Prepare yourself.

By blazemanxd, made worse by twistedsynapse

Oh, bother.  I'm so stuffed with fluff.  I'm dummy thicc.  

A Pooh edit that gives him honey projectiles and VERY aggressive A.I.

By KGenjuro, edited by an unknown author, edited again by blazemanxd

Griffon from KOF '03, edited for Another KOF

By Lifeend/Modified by oscar12345 ||| AI Patch by GUMHOY DAAAAAAH