ASAP PMozu

Prep:

Sell the Goddess Icon.

Cav Male MU needs 9 str 11 spd min to 6 turn. Survival is potentially an issue over many extended battles so may need to buy def/hp tonic. Having 12 str before any boosts allows Corrin to use the Bronze Lance for some of the map to build Lance WEXP and eliminate Yato's defence drop, which can help with survival.

Silas very likely needs a Str and Spd tonic (at base speed he gets doubled by the boss), might need a Def tonic. There's a single level you can check to see if you get a speed proc on if you want to be a cheapskate. You get a He can get Lance WEXP here and there depending on str but I'm not gonna bother listing all the combinations, you'll probably be using the Iron Sword mostly.

Positioning

Felicia goes bottom left, Silas with Effie top left.

Turn 1

PP
Silas moves 2 tiles below the top Facelss in the first group. Elise and Arthur can stand anywhere not in range, except for 3R from Silas.
Corrin pairs into Felicia and she moves, swaps to Corrin and ORKOs the first Faceless.

EP
3 Faceless attack Silas, a Faceless attacks Corrin.

TUrn 2

PP
Silas moves 3 right. Elise with Arthur in pocket moves above Silas and heals.
Corrin moves south across the bridge. Use vulnerary if neccessary (very likely)

EP
3 Faceless suicide onto Silas.
4 Faceless suicide onto Corrin.

Turn 3

PP
Silas moves 7 left, swaps to Effie, drop Silas 1 down (free spot for Bronze Lance Silas)
Elise moves next to Effie, swaps to Arthur, drops Elise next to Silas
Corrin moves to tip of remaining bottom right faceless range and drops Felicia out to the left.

EP
1 Faceless attacks Effie (Elise's personal should disourage the Faceless from attacking Silas)
1 Faceless suicides onto Corrin

Turn 4

PP
Effie pairs into Silas
Arthur finishes EFfie's faceless
Elise heals Silas
So;as attacks the boss (should get a DG)
Corrin recruits Mozu and pairs into her, Moze moves one left one up and trades her weapon and vulnerary to Corrin, swaps, drop Mozu left or down
Felicia heals Corrin

EP
Silas fights the boss and two faceless
3 Faceless suicide onto Corrin

Turn 5

PP
Silas finishes off the top Faceless (it can attack him from the right too)
Arthur pairs into Elise, Elise transfer Arthur into SIlas and heals (transfer may be uneccessary, but the extra str will help if theres no VoF active and Silas hasnt procced any str)
Mozu pairs into Corrin
Corrin moves into range of the bottom left Faceless and drops Mozu up
Felicia heals Corrin (depending on hp values and what Silas needs you may choose to have Corrin Vulnerary instead and have Felicia take Mozu, not heal, or pair into Corrin etc.)

EP
Silas chips the boss, Faceless attacks Elise
Corrin kills another Faceless

Turn 6

PP
Silas finishes the boss (should be in VoF so should reach okay esp with Elise personal). He should have a DG ready for EP.
Elise runs out of range of the last faceless.
Corrin moves in range of the last two faceless. Depending on what happened on Turn 5, they may need to vulnerary, or they might have an open turn to chip a Faceless with the Naginata. Felicia might heal or pair up. Mozu might get to stand next to Corrin or might not, someone needs to swap Corrin hack to the Yato if they used the Naginata most likely.

EP
Last faceless should suicide on Silas and Corrin