|Voiced by||Laura Bailey|
|Weapon||Crossbow (IB2), Phelege (IB3)|
|Found in||IB: Awakening|
Infinity Blade II
Infinity Blade III
Isa (short for Isaline) is a Deathless friend and companion to Siris. She was introduced to the series in Infinity Blade: Awakening, later appearing in Infinity Blade II and the deuteragonist and a playable character in Infinity Blade III.
Isa is not native to Lantimor. She traveled there in search of the Infinity Blade for unknown reasons, but likely to sell. Isa usually speaks in a foreign language, and frequently makes errors when speaking in Lantimor's native language, the most notable one being her saying, "sewing chaos", instead of "sowing chaos".
She usually uses a crossbow as her primary weapon, but she has shown the ability to take down a large beast with her bare hands. At the end of Infinity Blade II, she is also shown approaching The Vault of Tears with a staff to free Siris. Isa performs a series of kicks and then stabs the enemy in the abdomen
After the events of Infinity Blade I, Isa raided the God King's castle in search of the Infinity Blade. When Siris returned to the area, he was attacked by Isa, who attempted to steal the Blade from him. After failing to procure the weapon, Isa convinced Siris to take her as an ally. She promised to lead him to the Worker of Secrets in exchange for the Infinity Blade if he died on his journey (though not by her hand). Isa and Siris began growing closer as they traveled. At one point, Isa again attempted to steal the Blade while Siris slept, holding her crossbow to his head. Foreseeing the incident, Siris had attached a transportation disk to the bow's trigger mechanism. He summoned the disk after awakening, disabling the weapon. After she attempted to fire the broken crossbow, Siris told her to leave. Isa begged him to allow her to stay. She stated that she wouldn't mind being tied up at nights if he would keep her as an ally. Although she had lost his trust, Siris was aware that Isa remained crucial to his mission if he was to find the Worker. He agreed to continue traveling with her as long as she led him to Saydhi, the information dealer. After tensions settled, they continued to exchange casual, friendly conversations as they had before.
Along their journey, Isa and Siris heard a call for help. Against Isa's wishes, Siris jumped into the clearing in an attempt to handle the situation. He saw a traveler surrounded by enemies, which he engaged in combat. Instead of running, Isa tried to assist Siris. By inhibiting an enemy, she saved Siris's life, but she was seriously wounded. The traveler (revealed to be TEL) agreed to heal her, but she did not regain consciousness for some time.
When Isa awoke, Siris forgave her for her past treachery, stating that "saving my life negates an attempt on it". They continued traveling until they reached Saydhi's Estate. Isa agreed to stay back while Siris entered and dispatched Saydhi's guards. After killing Saydhi, Raidriar appeared and tricked Siris into handing over the Infinity Blade. As Raidriar prepared to strike with the blade, Isa fired a crossbow bolt into Siris's forehead.
Siris awoke in a nearby Rebirth Chamber, Isa sitting beside him. She stated that she had known Siris was Deathless, based on his use of rings and his fighting ability. She cited this fear as the reason she had betrayed him, and as the reason she had killed him before Raidriar could strike - once fully charged, the Infinity Blade is able to permanently kill any Deathless. Isa sullenly departed, telling Siris that she was going to continue hunting the Infinity Blade.
She is not seen again until the end of Infinity Blade II, after Siris is betrayed by the Worker of Secrets. At the end of the credits, Isa is shown walking up to the castle, in the same way that Siris does whenever a new Rebirth begins.
In Infinity Blade: Redemption, Isa saves Siris, and unintentionally, Raidriar, by unlocking the Vault of Tears, and reveals to Siris that she organized a rebellion to defeat the Deathless while Siris was away. She herself then becomes Deathless by using a Pinnacle of Sanctification, a machine that can convert ordinary beings into Deathless. In the end, she is killed in the Worker's attack on the rebels but is reborn in Infinity Blade III.
In Infinity Blade III, Isa becomes a playable character that is crucial to the game's plot. She hunts down Terrovax, rescues Jensen the blacksmith, from his cell, finds out the location of the Worker's Ark after being defeated by Lelindre, and kills the Soulless Raidriar allowing Siris to confront Galath. After Siris defeats the Worker of Secrets, Siris and Isa embrace as they teleport out of the Workers hideout as it is destroyed. Upon reaching the safety of the hideout, they are reborn and the two kiss passionately. They then proceed to raise the reborn Worker as their own child.
- Isa, being foreign to Lantimor, makes frequent mistakes when attempting to speak the native language of Lantimor.
- In Infinity Blade Awakening, Isa pronounces the plural word for pen wrong, calling them p****. Siris choked on his water, and Isa not knowing what she said, asked him if he had two of them. Siris decides to play a prank on Isa so he asks her if she ever held a p**** in her life. When she said "yes, many times", Siris burst out laughing. When Isa asked what was wrong, Siris told her to look up that word again as it had a different meaning.
- Isa is derived from "Isis", a goddess in Egyptian mythology. Siris is derived from "Osiris", a god commonly seen as Isis' husband.
- The staff Isa has at the end of Infinity Blade II is not found in Infinity Blade III.
- Several tattoos can be seen on the under side of Isa's forearms, which can be seen when she wears the Wraith Plate.
- Sanderson, Brandon. Infinity Blade: Awakening. 1st edition. Salt Lake City, Utah: Chair Entertainment Group, LLC, 2011. eBook.