Final Fantasy XIII
As the Purge train enters the Hanging Edge, Lightning attacks the PSICOM soldiers aboard and frees her fellow captives. PSICOM forces fire on the train and a Manasvin Warmech brings it to a halt. Lightning and Sazh fight through the PSICOM forces and arrive at the Vestige where they discover Serah outside the Pulse fal'Cie Anima's throne. Snow, Hope and Vanille arrive, and Serah asks Lightning and the others to save Cocoon and enters crystal stasis, having fulfilled her Focus. Lightning and the group confront and destroy Anima, but are branded l'Cie before it perishes and the Vestige plummets to Lake Bresha, crystallizing it on impact.
Lightning and her companions awaken in Lake Bresha realizing they are now l'Cie. Upon being branded l'Cie, they all shared a vision of the legendary beast Ragnarok. They discover Serah's crystal form fused to the crystallized lake. Lightning reluctantly opts to continue onward to evade the army's closing net so the party departs, leaving behind Snow, who has chosen to dig Serah out. They find an airship in abandoned ruins at the lake's edge and use it to escape, but are attacked by pursuing PSICOM ships and crash in the Vile Peaks.
Lightning plans to go to the capital city of Eden to destroy its namesake fal'Cie that controls the Sanctum, blaming it for the Purge and her current situation. After a disagreement on their Focus, the group splits up: with Lightning going to Eden to take down the Sanctum, and Sazh and Vanille going the opposite direction to run from their fate. Followed by Hope and unable to send him back, Lightning lets him accompany her. Her patience wears thin as Hope becomes a liability and Lightning threatens to leave him. Her frustration summons Eidolon Odin to attack Hope. Lightning saves him and they defeat the Eidolon together, convincing her to let Hope travel with her and help him "toughen up".
At the Gapra Whitewood, Hope takes the lead and Lightning gives him her survival knife to boost his confidence. Hope intents to take revenge on Snow for his part in his mother's death during the Purge and when Lightning tells him the Sanctum is to blame Hope resolves in making both Snow and the Sanctum pay for it. Lightning tries to dissuade Hope by suggesting they visit his father.
In Palumpolum, Hope leads Lightning into the underground Nutriculture Complex to avoid PSICOM. Upon hearing Hope speak of the fal'Cie treating humans like their pets, Lightning realizes that having lived under fal'Cie care since birth, she had always been their pawn, and that her anger is over her protectors turning against her. Realizing she has dragged Hope into the same delusion of fighting blindly to make up for doubt and confusion, Lightning tells Hope their goals of vengeance are over and promises she will not abandon him. Soldiers led by Yaag Rosch ambush Lightning and Hope as they emerge in the Agora, but Snow and Oerba Yun Fang intervene to save them. Lightning escapes with Fang while Snow takes Hope. With wireless communicators the pairs agree to meet up at Hope's house. Hope wants to go through with his revenge against her wishes, and when Lightning tries to reason with him her plea never reaches him.
Lightning learns Fang is not only a Pulse l'Cie like herself, but an actual Gran Pulse citizen. Fang and Vanille were crystallized centuries earlier after completing their Focus, but awoke in Cocoon without knowing how or why, and were indirectly responsible for Serah being made a l'Cie. Lightning and Fang realize Pulse and Cocoon are more similar than they initially thought in how both worlds fear and hate each other. Fang tells Lightning how a l'Cie's brand indicates the amount of time until one becomes a Cie'th, and reassures Serah will wake from crystal stasis one day.
Lightning and Fang discover Snow and Hope in time to help the latter battle an Ushumgal Subjugator. Hope has abandoned his plan for revenge and returns Lightning's knife, and they promise to protect each other before the group proceeds to Hope's home. Lightning tends to the injuries Snow sustained from protecting Hope and apologizes for her behavior towards him. PSICOM attacks the house but disguised Cavalry soldiers intervene and during the chaos Lightning has Hope tie up his dad to make him appear like an unwilling accomplice.
The party boards the Lindblum and learns Sazh and Vanille are being held captive on the Palamecia, and that Primarch Galenth Dysley is overseeing the transport. The four l'Cie infiltrate the Palamecia to rescue Sazh and Vanille and once reunited, they confront Dysley on the bridge. He reveals himself as the fal'Cie Barthandelus, leader of the Cocoon fal'Cie, and explains their Focus is to destroy Cocoon by turning into Ragnarok and killing Orphan, the fal'Cie that sustains Cocoon. The party flees on a small airship, which autopilots them through Eden into the Fifth Ark hidden beneath the city.
The group's l'Cie powers are fully awoken and they encounter Cid Raines, who reveals he is a Sanctum l'Cie branded by Barthandelus with the Focus of aiding them as Barthandelus desires for Cocoon's destruction so the deaths of its inhabitants would summon the Maker, the creator of fal'Cie and humans alike. Raines rebels against his Focus by attempting to kill them. The party defeats Raines, but he transforms into crystal despite having defied his Focus. The group decides to follow his example and save Cocoon. Fang turns against them until Lightning and Vanille help her tame her Eidolon, Bahamut. The party finds an airship with a gate leading to Gran Pulse, and descends to the world below hoping to find aid in their quest.
After falling under attack by a wild wyvern, Lightning helps Fang summon Bahamut to save the party. They land and create a base camp in the Vallis Media but after days of searching find Pulse devoid of human life. Hope wishes for the others to leave him behind and his Eidolon Alexander appears. Lightning and Fang help Hope tame the Eidolon, and with their resolve renewed, the party decides to head to Oerba, Vanille and Fang's hometown.
The party crosses the Archylte Steppe into the Mah'habara Subterra and the Sulyya Springs, where Lightning and Snow promise to see Serah together after saving Cocoon. They ascend Taejin's Tower and ride a capsule down to the outskirts of Oerba, but find it abandoned. The group is confronted by Serah, who refers to Lightning by her birthname and asks the group to destroy Orphan to summon the Maker and save the world from despair. Serah is Dysley in disguise, who announces he has resigned as Primarch and appointed a revived Raines in his place to incite a civil war. He has his familiar, Menrva, transform into an airship for the group to return to Cocoon, and they do so to try and stop Dysley's plans.
Sazh crashes the airship into the Eden Grand Prix, and the party makes their way through Eden to Orphan's Cradle among the ensuing chaos. In the depths of the Narthex they find Dysley, who summons the crystallized Dajh Katzroy and Serah before the party and shatters them. Denouncing it as an illusion, the party fights Barthandelus and destroys him. His defeat awakens the sleeping Orphan, who wishes to be destroyed after centuries of not having a life, and attacks them.
Fang submits to Orphan's demands and agrees to become Ragnarok. After they try to stop her, Lightning and the others aside from Vanille are turned into Cie'th and attack Fang. Orphan tortures her to force her to transform but Fang's incomplete transformation is not strong enough to kill Orphan. The Cie'th party members relive the memories of their quest and are restored, believing their transformation was another fal'Cie illusion, and that they have seen something that resembled a new Focus. Lightning announces their new Focus is to save Cocoon and all of the party's l'Cie brands turn white.
Orphan's true form is vanquished and Cocoon begins to fall. Lightning and the others float away as Vanille and Fang transform into a complete Ragnarok, using their power to stop Cocoon's descent by forming a crystal pillar to keep it stationary above Gran Pulse. Lightning and the others enter crystal stasis, but are restored and find they are no longer l'Cie. Lightning is reunited with Serah and begins apologizing to her, but is cut short when Snow reminds they "have a wedding to plan". Snow reassures Lightning he will make Serah happy, and Lightning congratulates them.