Father and Son is the last Lightning Returns: Final Fantasy XIII main-quest you have to complete in order to unlock the Ultimate Lair and to finish the video game.
When you activate Father and Son you will start a series of sub-quests, but all of them are connected to the current main-quest because in order to complete them you have to retrieve 5 fragments, and help Sazh cure Dajh.
The main-quest Father and Son can be played anytime, but only after Lightning’s Chocobo learns how to glide, because it requires your presence in Eremite Plains, on an elevated platform.
You can also opt to play Father and Son after you finish all main-quests in Dead Dunes area.
Regardless, a good idea is to start it after you finish all Canvas of Prayers quests and side-quests in the game, because some of them will help you complete Father and Son faster.
Description: “Far in the north Lightning encounters her old ally Sazh living in a wrecked airship with his son, Dajh. Except that living is hardly the right word for the coma in which the unresponsive Dajh lies. His soul has left his body, and no pleas, no cries, seem to reach him.”
Requirements: Complete main-quest 3-2: Healing An Angel
Rewards: 5000 Gil, Recovery Item Capacity + 1 Maximum EP + 1, Afro & Yellow Chick Adornment, Dajh’s Patch Adornment
Assuming that you already played a large number of side-quest in Wildlands, by now you should know all areas. Start Father and Son by visiting the Crash Site in Eremite Plains (northernmost point).
Climb the ladder outside and talk to Sazh. After the cutscene, if you open the quest-log you should see that you have unlocked 5 new main-quests. To complete them you have to find five different fragments for Sazh.
Fragment of Mischief – Quest 5-2: Follow the Chocobo Chick
The first quest item is the Fragment of Mischief. To get it, approach the small blue Chocobo chick outside the wreck, turn left and open the sphere nearby.
Fragment of Smiles – Quest 5-3: Whishes on a Canvas
For the second quest item known as the Fragment of Smiles, travel to the Wildlands Station and talk to Chocolina, who agrees to give it to you if you complete the Global Canvas of Prayers Quest named Key to Her Heart; therefore, open the Canvas of Prayers Board and accept the quest.
Now, travel to the south-western road, south from Aryas Village. Climb the ladder to get on the street and look for another sphere located close to the blue device on the other side of the road. Inside you will find the Beloved’s Gift. Take it to Chocolina and she will give you the Fragment of Smiles.
Fragment of Radiance – Quest 5-4: What Soul Seed Traders Want
Before traveling to Luxerion, for the Fragment of Radiance, make sure you complete the Wildlands side-quest named Peace and Quiet, Kupo to get the Moogle Fragment. N
ext, take the train to Luxerion, and talk to Baird (Soul Seeds side-quest) in the Arcade sub-area. If you have Soul Seeds give them to Baird, and then he will ask you to give him the Moogle Fragment. In exchange you will receive the Fragment of Radiance.
Fragment of Courage – Quest 5-5: Battle’s Bounty
For the fourth fragment, you have to travel to Yusnaan after 7 PM. Go to the Slaughterhouse and talk to Zoe.
Accept the next fight and defeat the Zaltys using lightning-based attacks to stagger your opponent. If you win the battle you will get the Fragment of Courage.
Fragment of Kindness – Quest 5-6: Beyond the Sandstorm
If you completed all side-quests in the game, then you already explored the Dead Dunes. Return to the desert and check the path that leads to Oasis Lighthouse (Dry Floodlands area) looking for Cactair.
Cactair is similar to a Cactuar but it has brown hair. It is a special enemy, meaning that it is more powerful. Debuff Cactair using Deshell, Deprotect and Slow, and then deploy a series of physical attacks to kill the fast creature and obtain the Fragment of Kindness.
When you get the final fragment, return to the Wildlands and talk to Sazh. At this point, the final main-quest in the game ends.
Note: If you finished all side-quests and main-quests before the last day, you have two options. You can fast-forward the time and wait for the Final Day to come, or you can explore the Ultimate Lair and kill all Omega beasts. You will get a large number of rewards and also a secret ending; however, the Ultimate Lair is unlocked on Day 13.