The ''Episode Ignis'' downloadable content focuses on Ignis, and as with previous DLC episodes, runs parallel to the main story. As Noctis and Lunafreya undertake the Trial of Leviathan in Altissia, they come under attack from the Niflheim Empire. The battle devastates the city, and with Noctis exhausted by his confrontation with Leviathan, Ignis, Gladiolus and Prompto try to save him. When imperial soldiers occupy the city, Ignis is separated from the party and must go on alone. After liberating various parts of the city, he commandeers a boat and braves the worst of the fighting to find Noctis. Still cut off, Ignis enters an uneasy truce with Ravus, who seeks to protect his sister and capture Noctis for Niflheim, knowing that the Empire needs someone of royal blood to wield the Ring of the Lucii and harness the Crystal's power.
Despite their efforts, Ignis and Ravus arrive too late to save Lunafreya, who used the last of her strength to save Noctis despite being mortally wounded. Ravus is distraught and prepares to kill Noctis for his failure to save her, arguing that all Noctis does is ask those around him to make sacrifices for him. Recalling a promise he made to King Regis as a boy and spurred on by a vision of Noctis ' destiny to cleanse the Starscourge, Ignis intervenes and the two fight until Ravus sees a vision of Lunafreya 's spirit. Realising that his sister's death was necessary to stop the Starscourge, Ravus relents. Their truce is short-lived as Ardyn interrupts them, overpowering both of them. He taunts Ignis as he prepares to murder Noctis, giving Ignis enough time to put on the Ring of the Lucii. Ignis earns the favour of the Kings of Lucis long enough to use the Ring, but this costs him his sight. Knowing that he cannot stop Ignis, Ardyn retreats and Ignis and Noctis are taken to safety by Gladiolus and Prompto.
In a post-credits scene, Noctis thanks Ignis for staying true to his promise to Regis as the party prepares to confront Ardyn for the final time.
also contains an alternate timeline to the game called " Extra Verse" where Ignis chooses to play along with Ardyn rather than fight. He is taken to Zegnautus Keep in Gralea, where Ardyn leads him to the Crystal and reveals the truth about Noctis ' fate. Unwilling to accept this, Ignis puts on the Ring of the Lucii and fights Ardyn. He makes a pact with the Kings of Lucis to sacrifice his own life to save Noctis and defeats Ardyn, who promises to return as he fades away. Noctis, Gladiolus and Prompto arrive as Ignis lays dying; Noctis willingly enters the Crystal, but not before using its power to revive Ignis. Ten years later the four protagonists return to Insomnia, where— as in the original timeline— they kill Ardyn and cleanse the Starscourge from Eos. With the light restored, Noctis takes his place as king.