"Good gosh, Cuphead, no!"
—Mugman, begging Cuphead not to accept The Devil's deal, Introduction
Mugman is the deuteragonist of Cuphead. He is Cuphead's brother, and, like the rest of his family, lives on Inkwell Isle. He is played by the second player and can join or leave the game at any time. Due to his deuteragonistic role, Mugman formerly could not be controlled by the first player. However, as of the update in April 2019, the first player can choose to play as him instead.
Mugman is very similar in overall appearance to his twin brother Cuphead, with his head reminiscing a mug, wearing a black, long-sleeved shirt, white gloves, cyan shorts, and brown boots.
What's different about Mugman's appearance compared to his brother is having a cyan color scheme to replace Cuphead's red, a shorter straw, and a much bigger nose. His eyes are smaller than that of his brother. His head is also slightly thinner compared to that of his red brother.
If the player chooses "Yes" in the Devil's cutscene - triggering the bad ending - Mugman's nose, pants and the stripes on his straw turn a darker shade of blue, his handle is broken, and he gains red eyes and sharp teeth, like his brother Cuphead. He also has fire coming out of his head in artworks.
Mugman is cautious and a bit of a worrier. While he secretly loves the adventures Cuphead drags him into, he often frets about the collateral damage they might cause. He has a somewhat dorky nature and tends to over prepare for a battle rather than jumping right in.
Mugman is fun-loving like Cuphead, though he is shown to be careful and less rash compared to his brother, and acts as the voice of reason for him. This is shown when he begs Cuphead to not make the deal with The Devil, as that would end up costing them their souls in the introduction. (Cuphead went ahead anyway and the brothers were forced to work with The Devil for a bit as a result.)
In Inkwell Isle, Mugman lived a joyful and easygoing life alongside his brother, Cuphead. One day, the boys wandered far from home and ended up in the Devil's Casino despite the warnings of their caretaker, the Elder Kettle.
In the casino, Mugman and Cuphead worked together to gain a winning streak at the Craps table that surprised even King Dice himself. When the Devil approached, he offered the duo a bet: If the boys won, they get all the loot in the casino, but if they lose, the Devil will take their souls.
Mugman tried to stop his brother from rolling the dice, as he knew that gambling with The Devil wasn't a good idea. Unfortunately, his attempts were futile, as Cuphead had taken the bet and lost. The duo begged for The Devil to spare their lives, and was thus sent on a mission to collect his debtors' soul contracts by tomorrow at midnight in order to keep their own souls. Cuphead and Mugman fearfully ran back home to the Elder Kettle, who gave them a potion that gave them powerful abilities and told them to go along with what The Devil says for now.
After doing the tutorial, Cuphead and Mugman proceed to collect the soul contracts, battling bosses, playing through levels, and saving the Legendary Chalice. When they travel from Inkwell Isle One to Inkwell Isle Two, the Elder Kettle tells the boys that their strength is growing thanks to those soul contracts, and soon it will be enough to defeat King Dice in the battle and even the Devil.
Eventually, with all of the soul contracts in their possession, the boys run into King Dice, who is determined to kill them due to losing a bet. After King Dice is defeated, Cuphead and Mugman then meet up with the Devil, who was awaiting them in his office. What the pair does next depends on the choice that the players decide. If they give the Devil the soul contracts, Cuphead and Mugman become his personal lackeys and are turned into demonic cups, creating the "bad" ending. If they do not give him the soul contracts, the Devil will be outraged and battle them.
When the Devil is defeated, the boys accept his surrender and burn all of the soul contracts, releasing the residents from their eternal servitude to the Devil. The boys then went home and told the residents that they are now free from their debt. They are praised for their bravery and an all-day celebration was thrown as thanks. The boys promised to never get into trouble again and succeeded until the next time.
Finger Bullets - Mugman can create energy bullets by constantly snapping his fingers. He can also charge them up to preform an EX attack, which is usually a much larger bullet that hits multiple times. The type of bullets depend on what potion you buy:
- Peashooter - The blue default bullet. Can shoot non-stop with a long range.
- EX Move: Mega Blast - A huge fire ball that hits multiple times,
- Spread - Shoots red pyramid bullets the spread in 4 rows. Has a limited range.
- EX Move: Eight Way - Sends 8 large bullets all around Mugman.
- Chaser - Shoots green homing bullets. Has below average damage.
- EX Move: Chaos Orbit - Sends multiple homing bullets that attack. More bullets orbit Mugman and damages enemies that touch him.
- Lobber - Purple orbs that bounce twice before popping. Does a lot of damage but has delayed shooting.
- EX Move: Kablooey - A large orb that explodes on impact.
- Charge - An orange fiery horizontal spiral that can be charged to deal an above average amount of damage. Takes a long time to charge.
- EX Move: Radical Barrage - A large explosion that affects all around Mugman.
- Roundabout - A light blue boomerang-like bullet that can come back if it didn't hit something.
- EX Move: Jumbo Rebound - Sends a large boomerang bullet that hits multiple times.
Dashing - Mugman can dash a short distance in both mid-air and on the ground. With the Smoke Bomb ability, he can "teleport" while dashing and not take any damage.
Parry Slap - While in mid-air or flying his plane, Mugman can attack pink objects by turning his straw into a hand and slapping it, whether it be enemies, projectiles, or objects. Parry Sugar will allow Mugman to automatically parry whatever he jumps towards. This helps fill up the Super Meter, needed to perform a Super Art.
Resurrection - When Mugman dies, he can be resurrected when his heart, which is in the center of his soul, is parried. As long as Cuphead is with him and his soul is still on screen, he can return to fight.
Flight - While Mugman cannot exactly fly himself, he is a master pilot and comes equipped with his own blue fighter plane, complete with bullets
- Rapid Fire Bullets - The default bullets for the plane. Like the Peashooter bullets, Mugman can shoot multiple bullets and they have a long range.
- EX Move: Toothy Terror Missile - Simply known as "Attack," Mugman shoots a missile with a Toothy Terror mouth that does multiple damage.
- Mini Bomb - Shoots tiny nukes that do above average damage to the enemy but have a slow fire rate.
- EX Move: Magnet - Shoots multiple magnets that home in on the target.
- Size Reduction - In his plane, he can shrink himself to be part of the plane, making it easier to dodge attacks and increases speed. Mugman can still use his bullets while in this shrunken stage, but they do less damage and have a limited range.
- Super Bomb Transformation - As a Super Art, Mugman can transform into a giant bomb that explodes either on impact or the if duration timer runs out.
Energy Beam - The energy beam is the first Super Art to unlock. Using the liquid from his head, Mugman spills it as a horizontal beam that damages enemies.
Invincibility - As the second Super Art, Mugman crosses the astral plane by transforming into a large, eyeless version of his head that spits out a gold, sparkling, complete version of himself. This makes Mugman invincible for a few seconds before returning to his normal state.
Giant Ghost - As the final Super Art, Mugman sends his spirit out of his body. Unlike Mugman's spirit when he dies, his spirit is now larger and muscular. The direction the ghost goes depends on how Mugman is moving (i.e. if Mugman moves left, the ghost goes left). The ghost damages any enemies he is near. He does this for approximately 10 seconds before he disappears except for his heart, which goes slowly goes up. His heart can also be parried.
Astral Projection - With the last two Super Arts involve him going into the astral plane, it can be implied that Mugman has the special ability to enter the astral plane and have out of body experiences.
- Made of ceramic: 3 hits can kill him (4 while equipped with the Heart Charm and 5 while equipped with the Twin Heart Charm).
- Can't be resurrected without the help of Cuphead (likewise, Cuphead can't be resurrected without Mugman).
- In the beginning moments of a boss battle, Mugman will extend his straw and take a drink from the liquid in his head. After the update, he may sometimes extend his limbs and look around him.
- Like Cuphead, in the final boss (or failing the Mausoleum level) Mugman will quickly hop from foot to foot, waving his arms with a scared expression.
- According to an interview with Studio MDHR, the liquid inside Mugman's head is the essence of his soul.
- However, people believe that Mugman drinking himself is evidence that the cups hold vodka and/or beer in their heads.
- Just like how Cuphead seems to be based on Mickey Mouse except that Mickey Mouse's shorts are overalls and have the waist going up to the chest and having buttons and suspenders sometimes, Mugman seems to be based on Oswald the Lucky Rabbit, sharing a similar color scheme and being the brother of the protagonist.
- Mugman and Cuphead's animations (when they use the blue potion) may be a reference to when Popeye eats spinach.
- His name may be a reference to the video game character Mega Man, as the pronunciation of his name and as his color scheme is similar to Mega Man's. This is even further supported by the "Run N' Gun" stages, which was the base of Mega Man.
- According to Evan Skolnick, Mugman is an adolescent. However, in a Twitter response to a fan, the Studio MDHR describe Mugman as a "kidult".
- When you remove Mugman (Player 2) from the screen, his head disappears, and he turns into a headless skeleton, but then the bones turn into a pile of ash.
- Mugman became one of the spirits in the "Ready! Wallop!" event in Super Smash Bros. Ultimate, along with Cuphead, King Dice, and The Devil.