Dimentio has a very twisted personality. At first, he appears to be a very jovial character, but it is revealed further in the story that his intentions are much more sinister. He shows no remorse for any of those he has hurt, and is rarely seen to be afraid or confused, maintaining an eerily calm demeanor, even while performing heinous acts like murder and abduction. The only instances where Dimentio is surprised or shocked are those right after defeating him in battles, though he quickly regains his smile.
It's heavily hinted that he is insane, and displays many characteristics of a psychopath, which Tippi had actually called him a number of times. Even his catch card remarks that he's a psychopath. He has a perpetual smile, and often throws bizarre similes and metaphors at those around him. The fact that he sends Mario, Peach, Bowser and Mr. L to the Underwhere without flinching, cracking jokes even, enforces this insanity.
He has an extreme dislike for Count Bleck, along with his fellow minions. Dimentio has a particular hatred for Count Bleck because his reasons behind initiating the prophecy of the Dark Prognosticus are due to heart break, which Dimentio views as a weakness that he later exploits to weaken the Count. When in a meeting with the other minions, Dimentio often only spoke up to insult the other henchmen, or to trick them into doing something to advance his plans. He was standoffish towards Bleck, and only spoke to him to get information from him. Despite his clear hatred for Bleck, Dimentio understands the advantages of working under him, as being a minion of Bleck's allowed him to let everyone else do the work of gathering the heroes and the Chaos Heart for him, so he could later initiate his plot to destroy all worlds and recreate a universe in which he ruled.
Dimentio has also proven to be a very intelligent person. He was able to utilize everyone around him to the fullest of their ability (making themselves think they were killed, their usefulness had run its course), manipulate both Bleck, the other henchman, and Mario and his gang, and was the person who was able to unhyptnotize Mr. L, who was really Luigi, something not even Mario realized. It is this characteristic that makes Dimentio one of the most dangerous villains in the game.
Dimentio has the appearance of a jester, with a face resembling a traditional theatre Comedy mask. His face is split into two colors; one white side with a black eye, the other side black with a yellow eye. Though rarely seen, he does frown a number of times in the game, like when being hit. His eyes also turn upside down to make his face appear more like a Tragedy mask. He appears to have no arms, making his hands disembodied from him.
He wears a cloak striped with purple and gold, and a matching jester's hat. The baubles at the ends of his hat horns often rotate or bounce when Dimentio performs a particularly magical feat, such as forming an energy ball or warping people. He also wears black "pie catcher" pants, and curly tipped shoes.
Dimentio, being a magician, is capable of numerous magical feats. He usually snaps his fingers or waves his hands to perform these abilities.
He is capable of creating a compact field around himself or others, which he can fill with explosions. In battle, this is a devastating attack. Though he can apparently vary the power in the attack, since he was able to send Mario, Peach, Bowser, and Mr. L to the Underwhere (AKA World -1) with this technique. He also used it on himself and Luigi in an apparent suicide attack, though Luigi was merely knocked out, as Dimentio planted the seed of a mind controlling plant called a Floro Sprout into his unconscious. Dimentio later appeared to activate the Floro Sprout, and didn't appear to be harmed by his own attack.
Dimentio can also create explosions outside of these boxes, as seen when he confronted Mr. L in the ruined Sammer Kingdom.
He can also form magical orbs, which he uses as projectiles. He can shoot up to three at a time. His duplicates are also capable of using this attack.
Dimentio has a seemingly unlimited ability to duplicate himself. In battle, he never creates more than two other clones, who are just as powerful as him and can use the same attacks and abilities, though they cannot be hit and will only vanish when the original Dimentio is hit. As seen in the final chapter, Dimentio had cloned himself hundreds of times, filling a long corridor with a sea of duplicate Dimentios, though they didn't hurt, or even attack Mario. They merely floated about the hall, and would push Mario away from the hidden chests that held the key needed to advance through the castle. They could be dispersed with Boomer or Cudge.
Like Mario, Dimentio is capable of flipping through dimensions at will, and will do this while fighting. Dimentio also has some lesser abilities that aid him in gathering information, such as his ability to levitate, become invisible, and teleportation. He can also warp others, as demonstrated several times in the game, notably when he played a game of "Tag" with Mario, sending him through the past worlds before actually fighting him.
Most battles with Dimentio take place in a dimension of his own creation, which he calls "Dimension D". In Dimension D, Dimentio's powers are apparently multiplied by 256. This is a reference on how scores in various games are stored as an 8-bit (1-byte) value. An 8-bit value can only go up to the number 255. Once you reach 256, the value is reset to 0 (and thus, nothing happens in Dimension D, and it is just a place where Dimentio prefers to fight in).
Dimentio has also displayed other abilities that he only uses once, such as somehow short circuiting Fracktail.
- His name is a combination of "Dimension", which he is known for controlling, and "Dementia", due to his unstable mental condition.
- Dimentio is never seen walking in the game. He is always floating, except for brief instances where he stands on the ground. Even when a Sleepy Sheep is used on him, he sleeps in midair.
- Strangely, Tippi recognised Dimentio upon his first appearance in the game, hinting that she knew him beforehand.
- If you listen to the storyteller in Flopside, he will tell you about Dimentio. According to him, Dimentio had befriended Count Bleck on his own accord, and volunteered to be a follower of him. Bleck turned Dimentio down for unknown reasons, but later allowed him to join him when he read about someone matching Dimentio's description in the Dark Prognosticus. Dimentio's role in the Dark Prognosticus, along with him stating that Count Bleck wasn't reading the prophecy correctly hints that Dimentio may have been the one to have authored the Dark Prognosticus.
- Even though its assumed that Dimentio was killed after the battle, he cannot be found in the Underwhere or Overthere, which could likely hint he is still alive and might have teleported away as the head of Super Dimentio exploded.
|Main characters||Mario • Luigi • Princess Peach • Toad • Yoshi • Paper Mario|
|Supporting characters||Dr. Mario • Princess Daisy • Rosalina • Wanda • Donkey Kong • Diddy Kong • Pauline • Professor E. Gadd • Toadette • Toadsworth • Captain Toad • Birdo • Nabbit • Cappy|
|Enemies||Bowser • Bowser Jr. • Koopalings (Larry Koopa / Morton Koopa Jr. / Lemmy Koopa / Wendy O. Koopa / Iggy Koopa / Roy Koopa / Ludwig von Koopa) • Wario • Waluigi • Fawful • Kammy Koopa • Dimentio • Antasma • Kamek • King Boo • Petey Piranha • Tatanga • Wart • Foreman Spike|
|Major villains||Donkey Kong | Bowser | Foreman Spike | Wart | Koopalings (Ludwig von Koopa | Lemmy Koopa | Roy Koopa | Iggy Koopa | Wendy O. Koopa | Morton Koopa Jr. | Larry Koopa) | Tatanga | Virus | Wario | Kamek | Baby Bowser | Smithy | Big Bob-omb | Whomp King | Waluigi | King Boo | Shadow Mario | Petey Piranha | Bowser Jr. | Cackletta | Fawful | Antasma | Sir Grodus | Lord Crump | Shadow Queen | Princess Shroob | Count Bleck | Dimentio | Pom Pom | Boom Boom | Bowser Soul | Topper | Hariet | Rango | Spewart | Madame Broode|
|Minor villains||Blooper | Bob-omb | Boo | Bullet Bill | Buzzy Beetle | Chain Chomp | Cheep Cheep | Dry Bones | Goomba | Hammer Bros. | Koopa Paratroopa | Koopa Troopa | Lakitu | Magikoopa | Monty Mole | Ninji | Piranha Plant | Pokey | Shroob | Shy Guy | Snifit | Spiny | Thwomp | Whomp | Wiggler|