Dr. Eggman

Dr. Ivo Robotnik, better known as Dr. Eggman, is the primary antagonist in the  franchise and the arch nemesis of Sonic the Hedgehog, much in the same manner as Bowser's conflict with Mario. However, in a similar vein to the aforementioned Mario characters, he has occasionally teamed up with Sonic to face greater threats in their homeworld and has friendly sports competitions with him in the Mario & Sonic series. He is a genius with an IQ of 300, and his goal is to dominate the world and build the Eggman Empire.

Dr. Eggman appears in the Mario & Sonic series as a playable character. He is voiced by Mike Pollock, who has voiced the character in the game series since .

Mario & Sonic at the Olympic Games
Dr. Eggman, as well as several other Sonic the Hedgehog series characters, appear in the Olympic crossover game Mario & Sonic at the Olympic Games. He is a Skill player, despite his rather large size, and he's also unusually fast. However, Dr. Eggman is lacking in power, and his stamina is weak.

Mario & Sonic at the Olympic Winter Games
Eggman appears as a playable character in the sequel Mario & Sonic at the Olympic Winter Games, and appeared in the first trailer for the game along with Sonic the Hedgehog, Mario, and Wario. He is again a skill type character. In the DS version of the game, he is one of two main antagonists of Adventure Tour along with Bowser. He and Bowser try to stop the 2010 Olympic Winter Games by capturing all the snow spirits. They would like to make their own Olympic Games, but Mario, Sonic, and their friends stopped Eggman and Bowser.

Mario & Sonic at the London 2012 Olympic Games
Dr. Eggman appears once again as a Skill type playable character in the Wii version of Mario & Sonic at the London 2012 Olympic Games. He has a very high Technique level and performs well at events such as Gymnastics. He appears alongside all of the other athletes at the start of the game's opening, as well as later appearing competing in Badminton - Doubles and Track Cycling - Team Pursuit. An outfit based on Dr. Eggman can be unlocked for Miis to wear.

In the Nintendo 3DS version, Dr. Eggman is included in the Tricksters class and is hence only playable in certain Events. In the Story Mode, Dr. Eggman first appears in the opening, in which he and Bowser reveal and begins his plan to cover London with Phantasmal Fog to prevent the Olympic Games from happening as they had not been invited. Dr. Eggman is then discovered to be partially behind the appearance of the fog in The Mysterious Thief when Rouge remembers that he brainwashed her, and also in Enter Bowser?! when Bowser Jr. accidentally mentions him having discussions with Bowser. Toad reveals that he heard Dr. Eggman was at the British Museum in Mario and Sonic, and he and the Heroes group later find Eggman Nega there filling in as a favour. They later find out that Dr. Eggman had visited the museum to gather information about the Phantasmal Fog. Wario later encounters Dr. Eggman and defeats him in an Event in an attempt to destroy a Fog machine and get some money, but the machine is revealed to be a hologram and Dr. Eggman escapes. Wario and Waluigi later find him with Metal Sonic, and defeat them in an Event to destroy the real fog machine and try to get some compensation. In The Banana Incident, it is also revealed that Dr. Eggman had installed a chip in Omega to have him perform task for him. In Clear Skies Again, it is revealed that the Dr. Eggman Wario and Waluigi cornered was a hologram, and Dr. Eggman releases the fog over London once again. In To the Ruins!, Omega recovers enough of his memory to establish more of the details of Dr. Eggman's plan, as well as revealing his lab to be within Big Ben. In The Grand Showdown, Mario, Luigi, Sonic and Tails arrive to confront Dr. Eggman and Bowser, who have been powered up by the Phantasmal Fog, and Mario and Sonic defeat them both in an Olympic Event. After the fog is sealed away, Dr. Eggman and Bowser reveal their motives for their plan, and Toad calls them over the walkie-talkie to inform them that they can still compete if they go to the Main Stadium, and the pair accept the offer, later appearing at the opening ceremony. Dr. Eggman is mentioned to be causing trouble with his robots in the first two Challengers bonus episodes, and appears in Junior Triumphant, in which he agrees to let Bowser Jr. challenge Metal Sonic, aiming to help refine the robot. Dr. Eggman also appears in the Tricksters Bonus episodes, in which he trains Metal Sonic to improve him for the Olympic Games, first against Waluigi, and later against Wario, from whom he obtains the Fog urn. In The Fog Returns, he uses the Phantasmal Fog from the urn to create a Fog Imposter of Sonic, and later explains the history of the fog to Orbot, Cubot and Metal Sonic. Dr. Eggman's invitation is frequently referred to in the Girls Bonus episodes, as it is accidentally ruined twice, delaying the invitations being sent out, causing him and Bowser to investigate the delay in The Real Beginning. After losing to Peach and Amy in an event, the pair wait for their invitations, but find them dropped by some Toads and mistake them for love letters, causing them to leave and head off sightseeing. A badge of Dr. Eggman can also be obtained from the badge machine.

Mario & Sonic at the Sochi 2014 Olympic Winter Games
Dr. Eggman also appears in Mario & Sonic at the Sochi 2014 Olympic Winter Games. He retains his role from previous titles, being a playable Skill type character.

Mario & Sonic at the Rio 2016 Olympic Games
Dr. Eggman returns yet again in Mario & Sonic at the Rio 2016 Olympic Games. In the Nintendo 3DS version, he is exclusive to 110m Hurdles and Equestrian.

Mario & Sonic at the Olympic Games Tokyo 2020
Dr. Eggman reappears in Mario & Sonic at the Olympic Games Tokyo 2020 as a playable character. Like many other Mario and Sonic characters in the game, Dr. Eggman wears outifts that are event-appropriate.

Super Smash Bros. Brawl
Dr. Eggman makes a cameo appearance as a collectible trophy in Super Smash Bros. Brawl, which is obtained by collecting over 500 stickers. He also appears as a sticker which increases a character's launch resistance by 39 points.

Super Smash Bros. for Nintendo 3DS / Wii U
Dr. Eggman makes a cameo appearance as a trophy in Super Smash Bros. for Nintendo 3DS / Wii U.

Super Smash Bros. Ultimate
Dr. Eggman appears as a Spirit in Super Smash Bros. Ultimate.

Profile
''Although the devious Dr. Eggman has great Skill-based abilities, he also is quite powerful. His huge, lumbering frame doesn't give the impression that he would be good at gymnastics, but believe it or not, he can handle the trampoline and vault quite well.''

Super Smash Bros. for Nintendo 3DS / Wii U trophy
Blue indicates exclusive to the Wii U version.

Trivia

 * Dr. Eggman appears alongside Bowser and Zangief in the Disney film Wreck-It Ralph.
 * Dr. Eggman's second Japanese voice actor Chikao Otsuka also voiced Wario in the Japanese commercials for Wario Land games.
 * Although his profile in Mario & Sonic at the Olympic Games states he is quite powerful, Power is one of his lowest stats in the game.