■Ryu vs Liu Kang: They're both the quintessential fighting game main protagonist.
■Ken Masters vs Kung Lao: The best friends of the main protagonists who had also trained alongside them. They also have friendly rivalries with them.
■Guile vs Jax Briggs: They're the tough military men. They've also worked alongside two earlier compared fighters (Chun-Li/Sonya) and also hold personal vendettas against a villain (M. Bison for killing Charlie/Kano for wiping out his unit).
■Cammy White vs Sonya Blade: Both are Feminine blonde military fighters.
■Chun-Li vs Kitana: Both are female fighters dressed in blue. Both lost their fathers to the primary villains of their franchises (M. Bison killed Chun-Li's father/Shao Kahn killed King Jerrod while merging Kitana's homeworld of Edenia with Outworld) Both have some sort of warm relationships with main protagonists of their universes (Ryu/Liu Kang)
■Zangief vs Goro: Both are really strong and both of them have a similar skin tone
■Blanka vs Moloch: Both Monsters with Green skin
■Dhalsim vs Quan Chi: Both Sorcerers
■Dan vs Mokap: Both are comedic relief warriors who cannot be taken seriously
■Fei Long vs Johnny Cage: They're both martial artist actors initially based on real-world martial artist actors (Bruce Lee and Jean-Claude Van Damme respectively)
■T. Hawk vs Nightwolf: Traditional Native American fighting game characters.
■Guy vs Sub-Zero
■Rufus vs Bo Rai Cho: Both fat and used for comic relief
■ Rose vs Sindel: Purple clad women with strong connections to the franchises main antagonists (Sharing a soul with M. Bison/Marriage to Shao Kahn). Their minds were also once overtaken by said villains (Once the host to M. Bisons consciousness/Brainwashed into loyalty to Shao Kahn.) They both have strong mystic abilities, that also allow them to use something of theirs as a whip like weapon (Rose's yellow scarf/Sindel's prehensile hair).
■Gen vs Shang Tsung: Both old and sorcerers
■Balrog vs Kano: Both are brutal, tough fighters who are members of criminal organizations (Shadaloo and Black Dragons). Both were recruited by the main villains of their respective franchises (M. Bison/Shao Kahn) to join them, and both rose high into the ranks. Eventually leading them to very important positions (M. Bison's enforcer/General of Outworld's armies).
■Vega vs Baraka: They're the blade wielding villains. Ironically that has a great battle of the "beauty and the beast" dynamic.
■M.Bison vs Shao Kahn: The antagonists considered the main villains of their respective franchises, even if they're not the main villains of every single game. Both were introduced in the second installments, and are immensely powerful.
■Seth vs Noob Saibot:
■Akuma vs Scorpion:
■Gouken vs Raiden: Both who are mentors to the main protagonists (Ryu/Liu Kang).
■Oni vs Shinnok:
·Cody Travers vs. Smoke:
·Juri vs. Mileena: Both are psychotic female fighters.
·Rolento vs. Darrius: Revolutionary based-fighters.
·Sodom vs. Kabal :
·Dudley vs. Mavado:
·Oro vs. Ermac: Both are mysterious and immensely powerful red-clad fighters with telekinetic powers.
·Rashid vs. Fujin: Both are windy fighters
·Sakura vs. Li Mei: Both are practitioners of the same arts as the lead protagonists (Sakura learned martial arts by studying Ryu and copying his moves/Li Mei learned from Shujinko, a former student of Liu Kang's mentor Bo'Rai Cho).
-Kolin vs. Frost: Both are female ice fighters.
·Ibuki vs. Kira:
·Poison and Hugo vs. Ferra and Torr: Both are tag team fighters
·Crimson Viper vs. Ashrah: Both are mysterious beautiful women with mysterious allegiances. Crimson Viper was hired by S.I.N. but is also an agent for the US government. Ashrah is from the Netherrelm, but acts as a demon hunter.
·Alex vs. Shujinko: Both who are the games new protagonists from each series (Street Fighter 3/Mortal Kombat: Deception).
·Elena vs. Jade:
·Sean vs. Kai:
·Juli vs. Skarlet: Other female servants to the lead villains (M. Bison/Shao Kahn).
·Necro vs. Cyrax: They're both the victims of twisted experiments committed by dark organizations (Illuminati/Liu Kuei). Both however eventually became self-aware once again and turned against them. Through the experimentation both got a wide array of abilities.
·Twelve vs. Sektor: Fellow, evil experiments created in the same projects as the two above heroes. (G-Project/Cyber Ninja Project). Both are evil and archenemies with those characters, and also like them have a vast array of powers.
·Hakan vs. Kintaro:
·R. Mika vs. Sheeva: Both are Female wrestlers.
·Birdie vs. Motaro:
·Adon vs. Reptile: They're both slimmer villains who at least once served under two villains compared later (Sagat's student/Shang Tsung's guard).
·Garuda vs. Onaga:
·Gill vs. Blaze: Immensely strong elemental powered villains. Both have control over the power of fire (though Gill also has the ability to control ice, a possible advantage). Also both are in story chronology the latest final bosses.
·Yun vs. Taven: Both Brothers with someone else [Yun + Yang and Taven + Daegon
·Yang vs. Daegon: See above
·Karin vs Nitara
·Remy vs. Rain
Necalli vs. Kotal Kahn: Both are evil fighters based on the aztec mithology
·Allen Snider vs. Kobra
·Ace vs. Chameleon: Both are warriors who can mimic the attacks from other fighters, although Chameleon can only copy the MK Ninjas.
·Ingrid vs. Khameleon:
·Pullum Purna vs. Tanya:
·Hokoto vs. Sareena:
·Cracker Jack vs. Dairou:
·Skullomania vs. Meat:
·Doctrine Dark vs. Drahmin:
·Sawada vs. Hsu Hao:
·Blade (Street Fighter: The Movie) vs. Jarek:
·Vulcano Rosso vs. Hotaru:
·Shadowgeist vs. Havik:
Sagat vs. Kenshi: Both have eyesight problems but make up for it in other ways [ Sagat + Extremly Powerful and Kenshi + Telepathy]