V: Endless Dawn (伍：淡く光満ち, Go: Awaku Hikari Michi lit. 5: The Pale Filled Light in the Japanese version) is Xenologue 19 of Fire Emblem Fates.
Tensions are still high between the two groups, still distrusting each other after Shigure told the truth to both sides. The only people unaffected by this are both Kanas, who believe that Shigure can help them. However, Arete teleports in and tells them to withdraw or die. Shiro and Siegbert attempt to attack her but are repelled by her counterattack. Arete decides to teleport everyone except both Kanas and Shigure before calling in the Vallite army to kill the intruders.
During the battle, some of the children arrive to assist in the fight. Sumeragi, Arete and Mikoto fight off the children but are eventually defeated in battle. Mikoto is surprised to see two children looking extremely similar to Corrin and asks them to save Anankos before dissipating into water, but not before opening the path to them.
The remaining children that did not arrive into the battle appear, with both sides gaining each other's trust in battle. When the group arrives at Castle Gyges, both Kanas decide to use their Yatos to create the Omega Yato but are stopped by Shigure. Shigure reveals the actual truth to them, planning to go alone to absorb the curse to save other realms at the cost of him suffering alone. He tells them that each of the children came from different realms Anankos invaded and that in those realms, the war was favored for either Hoshido or Nohr and that the Silent Dragon was still sealed. He tells them that his world was an exception, with both sides working together to fight Anankos, but failed and were killed in battle. Shigure decides to use a translocation crystal to teleport everyone out of the chamber, much to everyone's protest before heading on alone to face Anankos.
Subjective: The following part of this article is based upon the editor's personal experiences and opinions, and therefore may not be applicable for all readers.
The objective of this Xenologue is to beat the three Vallite bosses (Sumeragi, Arete and Mikoto). All the royal children are promoted units now (excluding Shiro and Forrest, who were already promoted in the previous four Xenologues). Mikoto is in the middle path while Sumeragi is in the west and Arete in the east.
Players start off with both Kanas and Shigure in the middle island. At the end of turn 1, Shiro and Siegbert will arrive from the western island. At the end of turn 2, Kiragi and Forrest will arrive from the eastern island. At the end of turn 3, several more children will arrive; however, they only get a little boost in their stats rather then being promoted units. Mitama and Dwyer arrive in the middle path, Ophelia, Nina and Hisame from the west, while Asugi and Soleil will arrive from the east.
Trigger Sumeragi's group in the west side (preferably after defeating the wyvern reinforcements) by luring the Dark Knight into attacking one of your units. It's Speed Thunder will help your units in the west to avoid getting doubled by Sumeragi, who starts off with the Hagakure Blade. Unless you have enough units to surround and attack Sumeragi, do not have Ophelia stand next to him; even though her Heartseeker will negate the Hagakure Blade's avoid bonus, Sumeragi can easily defeat her. Try to have Sumeragi stand on a fissure tile; it will reduce his defense by 1 and his evasion by 20, negating Hagakure Blade's bonus. This does stack with Heartseeker, although you will need to deal with Sumeragi quickly before he can attack. Even after all that, make sure the Hero accompanying Sumeragi attacks either Shiro OR Siegbert with Ophelia out of the way so she doesn't die. For this strategy to be fully effective, it is best to try and get Shigure to go to the west as well to give an assist, and if possible or necessary, have Shigure carry one of the Kanas as well.
Arete's group in the east is slightly easier; only the two Great Knights next to her will move. The Great Master behind her does not. A high resistance unit can easily take the both of them out, as the Great Master is carrying a Bolt Naginata. Along with that, Soleil carries an Armorslayer, which means she can deal serious damage against the Great Knights.
When Sumeragi/Arete are defeated, they will help the player by activating the Dragon Vein to weaken the crystal barrier around Mikoto. Both of them will need to be defeated in order to break part of the barrier for your units to go in. This may be the hardest part of the Xenologue, as all six enemies (Mikoto included) are carrying ranged weapons. Players can use Dwyer's Entrap staff to forcibly teleport one of the Bow Knights to lower the amount of attacking enemies when both Sumeragi and Arete are defeated. Mikoto will need to be taken out quickly, because she can deal a large amount of damage, has Renewal, Vantage and Darting Blow which can easily defeat the children. If her health is low, she will swap places with a General (carrying a Silver Javelin) and delay the player even more. Mikoto is also carrying an Enfeeble staff, so be wary that she can weaken your units if her staff hits.
To ensure Mikoto's defeat, try to have all your units be around her, but out of her attack range. Ophelia is essential for the strategy to be a success, as by merely standing next to her, the Heartseeker ability will reduce Mikoto's ability to dodge, and allow the legendary weapon holders to deal damage to her, as they are essentially the only units able to deal real damage to her without much fear of being countered and killed. It is advised to have Shiro attack Mikoto first (with a speed boosting pair up); she will be unable to attack him due to having no accuracy, and to lower her defense and speed. Pair the remaining legendary weapon holders, especially both Kanas, so the two could double MIkoto. This way, even if a Dual Guard triggers for MIkoto, a second attack can be made to further dwindle her HP.
Players are advised to rush this Xenologue rather then taking their time. This is because over time, endless waves of Faceless and Stoneborn come from the starting positions of the royal children, and it is near impossible to fend off all of them.
Note: Rewards are only given if all children survived the battle.