The Conqueror (覇王ヴァルハルト Haō Varuharuto lit. Overlord Valhalt in the Japanese version) is Chapter 19 of Fire Emblem Awakening. This chapter takes place in Valm Castle, even though Chrom's army are approaching it.
The script for this chapter can be found here.
|The following part of this article contains strategy; therefore, it is subjective, and may not work for everyone.|
One possible strategy which can be used to complete this chapter in one turn is to use:
-A unit with 'Galeforce' skill and one of the following: a ranged weapon and 8 movement OR more than 8 movement
-A powerful unit which will be able to defeat Walhart in a single combat
Start by placing the unit with 8 or higher movement in the space diagonally up/left of Chrom, and the powerful unit within pairing distance (if they are the same unit, you don't need to worry about this). Start the battle and move the powerful unit to the far-moving unit and pairing up. Next, move them 1 space (2 if possible) left and 7 upwards, then defeat the Paladin to activate Galeforce. Next, move as close to Walhart as possible and switch to the strong unit. Make sure any other units you brought are safe, then end the turn. During the enemy phase, Walhart will attack your strong unit and kill himself, completing the chapter in one turn.
If you are not going for the one turn strategy, have your units trained up to withstand the onslaught of mounted enemies and Wyvern Lords that are spread out across the map.