Of the gang of playable characters in Borderlands, three are male and one is female, who are all with a fourth man driving the truck. The female is introduced as "The Siren," which is barely a gnat's whisker away from simply calling her "the token girl."
Potentially seen in Dragon Age: Origins, if the player character is female; if so, she's currently the only female Grey Warden in the Fereldan branch of the order (even before most of her fellow Wardens are annihilated in battle).
Dragon Age II describes the existence of the Forbidden Ones, a group of ancient demons who first taught blood magic to humans. Of the quartet, only the Undying Xebenkeck is identified as female.
Throughout the entire franchise, the heroes battle demons of all shapes and sizes, but only one kind - desire demons - is explicitly female in appearance.
Ensemble Stars! has Anzu as the only female student in her school's performance department. Apparently it runs in the family, as her brother from Ensemble Girls! served as The One Guy in a recently-integrated all girls' school.
Fatal Fury: The first game lacked any female fighters. In the second game, Fatal Fury 2, eight new fighters were introduced, including the first female fighter in the series; the kunoichi Mai Shiranui. By the third game, it's established that female characters are introduced every game, but due to rotating some of the female characters out of the games as well, it doesn't guarantee that a given work in the multimedia franchise will have more than one female.
The original version of Final Fantasy III stars the all-male Onion Knights; the remake for the DS makes one of them a girl.
Every single-player game since Final Fantasy IV has a rule to avert the Smurfette Principle. Exactly three female characters in the playable cast, regardless of the total cast size. This even extends to entries of small cast sizes, like Final Fantasy V (three women, two men) and Final Fantasy X-2 (an all-female party of three). Because later games have gravitated toward a total playable cast size of 6, Gender-Equal Ensemble is in effect.
For the longest time, Chica of the Five Nights at Freddy's fame is the only animatronic officially confirmed to be a female. The principle is averted as World adds another confirmed female (JJ) and Sister Location adds a number of new female animatronics.
Gate Of Doom, known in Japan as Dark Seal, has three male heroes (Knight, Bard, Ninja) and one female (Wizard).
The original has three male (Warrior, Wizard, Elf), one female (Valkyrie) characters.
Sequel Gauntlet Legends averts by making a Gender-Equal Ensemble; the androgynous-looking elf is a female elven Archer.
Seven Sorrows goes back to the original four characters.
The only women in the entirety of Half-Life are the black-clad assassins who never speak and only appear in two areas. Also, despite Black Mesa claiming to be an "equal-opportunity employer", all of its employees seen in the original are men, except for the holographic assistant in the tutorial. The cooperative expansion Half-Life: Decay for the PS2 fixed this by having you play as either Gina Cross (who apparently lent her voice and likeness to the holographic assistant) or Colette Green.
Halo 4 Spartan Ops: Fireteam Majestic begins with Tedra Grant (female) as part of the original Majestic line-up, along with Anthony, Carlo, Paul, and Gabriel (males). Naiya Ray is introduced in Halo: Escalation.
Kerbal Space Program added a fourth playable character quite late in the development process; originally the kerbals were a Single Gender Species. This can be seen as Invoking the Smurfette Principle because Valentina is a female clone of Jebediah, other than a slight stat difference (she's marginally smarter and more courageous), she's superfluous because the original 3 males already cover all 3 character classes (Pilot, Engineer, and Scientist). However, the game provides a method for the player to avert the Principle with an endless number of randomly-generated astronauts of either gender can be hired to adjust the crew's gender ratio as you choose.
Killer Instinct features eleven fighters. Initially, Black Orchid was the only female on the original cast of KI but when development started on season 2 of the 2013 game, it was revealed that Riptor is and always was a female, meaning the original KI actually had two female fighters.note Of course Riptor being a human-raptor hybrid meant there's still only one female in a group of ten humans.
While there are a small handful of important female NPCs, when it comes to the playable characters, the three main characters are all male, and there's only one female Guest-Star Party Member in each game; Ariel of The Little Mermaid in the first one, and Mulan of Mulan in KHII.
There's also Organization XIII. Out of thirteen members, there is only one female, that being Larxene. The creators originally planned on making Marluxia female as well, but changed their minds.
Left 4 Dead and its sequel justify their decision to use only three men and one woman as playable characters: The gene to be resistant to The Virus is recessive and carried on the x-chromosome. Women need two copies of the gene, while men only need one, explaining the genetically sound 3:1 ratio.
The Legend of Zelda: For a given game, the Zora characters have usually only one female among a sea of muscular-bodied males.
Mega Man (Classic): The villains use the following naming scheme — every Robot Master is called <word> Man. During Mega Man 9, one of the eight villains was Splash Woman, finally participating in the Smurffette Principle.
Despite being the flagship Action Girl of the video game world, Samus Aran of Metroid fame managed to become the Smurfette in her own series in Metroid Prime: Hunters. Six new bounty hunters were introduced, all of them male or ambiguously so. Metroid Prime 3: Corruption is more gender-balanced, as one of the three new hunters is another female.
Out of the dozens of characters in Modern Warfare, the only female character is your fellow Cobra pilot "Deadly" in the first game. Mostly justified by being a military game; while women are no longer barred from joining in a lot of places, real life militaries are still heavily male dominated.
Let's see, Mortal Kombat... For the first game, the creators realized they didn't have any female fighters in their roster, so they changed the character of male Kurtis Stryker into female Sonya Blade (Stryker would be re-added in the third game). This made her the only female out of 7 playable characters and 10 fighters overall. Later games have made sure to include additional female playable characters from the start.
All three games in the MOTHER series have a playable party consisting of three male characters and one female character.
Nezumi Man has Wave Nezumi, the only female boss of the eight.
In One Piece Mansion, Raspberry gets the descriptor of "The only female in Syndicate 5".
Robopon: In the first game, Miss Amron is the only female Legend out of seven.
In Scribblenauts Unlimited, Maxwell has many, many siblings you can unlock and play as. Most of them are brothers, but there is one sister.
In the first Shin Megami Tensei, all of the Seraphim (Michael, Uriel, Raphael, and Gabriel) were presumably male, but the second game reveals Gabriel is a girl, and all subsequent works within the multimedia franchise featuring Gabriel retain their revealed genders.
StarCraft: Brood War, the expansion set to the first game, added Protoss matriarch Raszagal (the only female Protoss).
Starcraft II expands the universe a bit, including adding supporting female human characters, but with Raszagal dead, the role of "only female Protoss" is inherited by Executor Selendis, who is the protagonist of the second expansion set.
Super Mario Bros.: The game series tends to avert the principle due to lack of cast, but some entries qualify;
During Super Mario Bros. 2, Toad (male) and Princess Peach (female) were added to Mario and Luigi (both male) as playable characters. The Divergent Character Evolution of the Mario cast would inspire later games to include Princess Peach as a playable character.
The Mario Party games began with a cast of six playable characters, with Princess Peach as the sole playable female character. This was changed in Mario Party 3 when Daisy was added to the cast.
When the Koopalings were introduced in Super Mario Bros. 3, Wendy O. Koopa was the only one of the seven siblings to be female.
Warcraft games: Out of all the 12 heroes available in the initial third Warcraft, only one is female (Priestess of the Moon). The expansion averts this by adding three more female heroes (Warden, Dark Ranger, and Naga Sea Witch).