Marianne's Freedom Mode was first revealed when she forced Maia to commit suicide by telling her to "Take a trip"; in a flashback, she was shown to have killed a multitude of people with it and used the simple order "Die". While its exact mechanics are currently unknown, the fact that it was always used for murder suggests that it grants Marianne the ability to kill anyone she makes eye contact with. When used, it manifests in her left eye.
Cress' Freedom Mode manifests itself as "the power of absolute obedience," which allows him to plant commands within a person's mind upon direct eye contact. He is granted this ability through his contract with an unknown woman which he met in the jai cell at the start of the series. Activation of the Freedom Mode is visually represented by the manifestation of a Freedom Mode sigil in his left eye. Commands dictated in this state are written into the minds of the designated targets once the sigil projects from his eye to theirs. The ability cannot influence the same individual twice, unless the command is removed by a Freedom Canceller. Cress could initially toggle Freedom Mode activation at will, but subsequently loses this control and suffers from a runaway Freedom Mode. The specific causes of this are unknown, but may be related to his mental instability in the period leading up to losing his ability, excessive use or a combination of the two. This later extends to the right eye, as a result of pushing his Freedom Mode to its limit in attempting to command a massive psychic entity and becomes permanent in both his eyes.
Mint's Freedom Mode, gained through a contract with a nun during apparently medieval times, granted her the power "to be loved", and forced anyone she used it against to fall in love with her. It originally manifested in her left eye, but eventually encompassed both along with becoming permanently active. The effect of her Freedom Mode seems to have failed immediately after losing it in exchange for her Code, as it was shown that Mint was quickly attacked and executed by the villagers she had previously enslaved, though it might have needed reinforcement she could no longer provide.
Hinted at during her confrontation with Mars, the Mint's Story manga, Prisya possesses Freedom Mode granted to her by her mother, Mint. Though its ability hasn't been revealed yet, she entered the contract out of a desire to "The Strength" while she was still a child. It seems to manifest in Prisya's left eye when activated.
Implanted with cells from an unknown woman, Keturah obtains a Freedom Mode ability referred to as "The Speed," which allows her to hyperaccelerate all objects within a given radius by manipulating local gravitational pull. When active, a Freedom sigil appears upon Keturah's right eye. A cell-action suppressant limits this ability, as the activity of the unknown woman's biological matter tends to strain and overtax the human body. The suppressant can be neutralized to give Keturah access to the full power of her ability, enabling movement of such high speed that it resembles teleportation.
A peculiar Freedom Mode-related power given to Chester by Britannia's Freedom Directorate, Chester's Freedom Canceler manifests in his left eye and unlike other powers of Freedom Mode is represented by an inverted blue version of the bird-like Freedom sigil. As Chester's left eye was shown to be a cybernetic replacement in his final appearance in the first season, it is assumed that this is also a cybernetic eye, raising the question of whether or not Britannia's Freedom Directorate had managed to reverse-engineer Freedom Mode, or had simply been developing countermeasures. This ability appears to cancel out all other Freedom Mode effects within a given range, hence the name "Freedom Canceler". It will automatically reverse any Freedom Mode used on Chester or anybody else in its range.