- A bizarre amalgamation of the Mutant bio-weapon and Black List's Ghost stealth technology was developed by an unidentified weapons manufacturer. Maiden has escalated the Mutant War to new heights.
Maiden is a female mutant character, and is the most popular mutant character in many CF servers due to it being one of the first purchasable mutant. She has slower movement speed than the Dread and the Slug but has a higher jumping height than that of the normal mutant, allowing her to reach higher platform easily. Slug form features gray arms with 2 Slug Nails in different positions depending on your hand set that is changeable in the misc tab of the options. Berserker changes the clothes and other aspects of the maiden to white, also giving her blue claws on her fingers for slashing and stabbing. Titan features a reskin of the berserker to red, with red claws and red dress.
By default, Maiden jumps higher than other mutant. Her [G Skill] allows her to temporary turn slightly invisible just like what the Black List Ghost armor functions. Unfortunately on Titan form, invisibility is poor, due to the transparent red color of the particles surrounding the Maiden and her clothes, making her much easier to see than her Berserker form. This skin is still very deadly however, because Soldiers often try to focus on Dreads and Slugs, so they pay less attention to Maiden's appearance. Often, Maiden can sneak into heavily defense position while the Soldiers are busy fending off other mutants, bringing easy win for the mutants.
Maiden 2.0 (aka Psycho Nano) is the new version of Maiden, featuring more dreadful appearances in Slug, Berserk and Titan form. Currently available in CF China.
- In CF Indonesia, Maiden is uniquely called as "Suster Ngesot" ("suster" is the Indonesian for "nurse", while "ngesot" is the Javanese for "walking dragged") which was a famous female ghost of an Indonesian horror movie with the same name who walks by dragging herself around in a quite hospital during midnight since she can't walk because she had her legs disabled upon died. However, Maiden in CrossFire still walks by her feet instead of dragging herself around.
- CF Vietnam features Maiden, along with Slug, inside a special Zombie capsules that contains RPK-Gold and Gatling Gun Gold as best prizes. Due to a coding error however, when players win her (30d), there's a global announcement stated "[IGN] has won [Maiden] from Capsule Shop", making her the only temp prize to receive global announcement when won. This glitch has been fixed in recent patches.
- In Hero Mode, the height of jump on the Maiden is nerfed to that of the normal mutant, to acquire the high jump she has, players must evolve into Berserker or above. This glitch is fixed in Hero Mode X.
- Due to a texture glitch, Titan Maiden appears to wear no panties, having only a semi-transparent black rectangle going about halfway around where they should be. Mutants will tend to try and get under Titan Maidens to see this, or players will kill themselves and watch survivors that have this mutant in third person to get a better view.
- The higher jumps and the ability to turn invisible has caused the Maiden to become the most hated mutant in CF Vietnam. If a Maiden infects a player not paying attention, breaking a defense, many players would blame it on the Maiden instead of trying to pay more attention on their surroundings. As a result, most Maidens aren't likely to last long in MM/HM/HMX rooms, even on high ranking servers.