Mortimer Mouse

Mortimer Mouse is Mickey Mouse's rival and second arch-enemy in animation, after Pete. Mortimer first appeared in the Mickey short Mickey's Rival and ever since he has been battling Mickey for Minnie's affections.

History
Mortimer's name was originally meant for Mickey Mouse but Walt Disney's wife Lillian thought the name made Mickey seem pompous. Years later, the name would be used for a new character created to be a rival for Mickey. Mortimer only appeared in the cartoon "Mickey's Rival" and was never seen again until 2000 when Mortimer's popularity skyrocketed and landed him roles in several Mickey Mouse related material.

Design
Mortimer is essentially a taller version of Mickey Mouse, and seems a bit more human-like. Unlike his rival, Mortimer has whiskers, perhaps referencing how he has a ratlike persona. He has feet the size of Goofy's. Unlike most of the other mouse characters, however, you can see two large teeth close together, like a rat. He is usually wearing jeans and a shirt, but sometimes he also wears a hat.

Personality
He is said to be Minnie's ex-boyfriend and she possibly left him due to his nature. He is very arrogant and rude, the total opposite of his rival. While he claims he loves Minnie, he shows to be incredibly selfish as seen in the cartoon "Mickey's Rival" where he leaves Minnie to be attacked by a bull that he provoked. Not only that, he attempts to flirt with any female character on screen which might also indicate the reason the relationship between him and Minnie was abolished. Also, Mortimer can be rather sexist as seen in "Mickey's Rival Returns" where he feels that Minnie is only a prize to be won.

Mickey's Rival
In his first appearance, Mortimer was driving by and notice Mickey and Minnie as they were having a picnic. Minnie is thrilled to see Mortimer once again. As soon as Mortimer walks up, Mickey already knows he is bad news just as Mortimer does not like Mickey at all so he attempts to humiliate Mickey and when Mickey shows Minnie how upset he is Minnie states that he is just jealous. Mortimer then tries to impress Minnie by annoying a bull that is over a fence. The plan works until the bull finds a way out. Mortimer rushes and drives away in his car and leaves Mickey to rescue Minnie who eventually remembers why she left Mortimer in the first place.

Mickey Mouse Works
In this series, Mortimer is once again the main antagonist along with Pete. Here, Mortimer is Mickey's neighbor and is still competing with Mickey to win Minnie Mouse's heart. In the series, Mortimer is apparently wealthy having far more advanced technology than his rival. One of Mortimer's most villainous roles was in the cartoon Big House Mickey where he accused Mickey of robbing his house having Mickey sent to prison. Mortimer made a guest appearance in the Pluto segment; Pluto Gets the Paper.

Mortimer's first appearance in the series was the cartoon Mickey's Rival Returns. In this cartoon, Mortimer and Mickey compete with each other in volleyball. The winner gets to ask Minnie on a date. Originally, Mickey refused the idea being that it would be using Minnie as "some kind of trophy", but Mortimer's arrogance angers Mickey into competing. Mickey wins, but Mortimer reveals the competition prize to Minnie having her beleive Mickey thought of her as a prize. Minnie instead leaves with Mortimer but at the date, he begins to harass her for a kiss. Fortunately, she is saved by Mickey who she forgives and has a beach dinner with,

House of Mouse
In the television series House of Mouse, Mortimer gets a role as a recurring character. Mortimer appears many times as a guest and tries to trick Mickey or Minnie into breaking up. In the series pilot episode, Mortimer appears but is seen flirting with Donald Duck's girlfriend Daisy Duck instead. Mortimer proves to be hated by mostly all of the guest at the club ranging from heroes to princesses to villains despite being one himself. It is even indicated in the episode "Pete's Christmas Caper" that the cruel Pete might even have a disliking towards him.

Arguably Mortimer's most famous appearance is where he tricked Mickey and friends into believing he was the club's critic and forced everyone to treat him like a prince or he'll give them a negative review which could close the club. Mortimer is foiled when the real critic reveals himself to be Lumière from Beauty and the Beast.

Role in Ultima
In Ultima, Maleficent recruited Mortimer to the Organization as one of her new apprentices to counter the resurgance of keyblade wielders in the Society. As a result of his training in use of nothingness from Xemnas, use of darkness from Ansem SOD, and use of Keyblade wielding from Master Xehanort, Mortimer has become a much more deadlier adversary to Mickey Mouse and might actually prove to be a worthy opponent to Sora, the chosen one of the keybearers. Of course, he's still as arrogant and cocky as ever, and that may prove to be his fatal flaw in combat.