Grand Hero Battle - Clarisse

I swap Azura and Olivia for infernal and lunatic.

First you want to break the wall using Xander and let him take the defensive tile while the others stay at the back. (most of the enemies will attack him)

The rest is easy. Just pull Xander back for healing while Reinhardt's cleaning up the mess.

(Lunatic) https://youtu.be/PN7seX0YbV8
(Infernal) https://youtu.be/39-0uIBezxU

Pretty much what the title suggests.

Heroes used as well as the skillsets I used:

Xander: Siegfried, Reposition, Retribution, Fury 2, Threaten Defense 2.

Camus: Gradivus, Ardent Sacrifice, Glimmer, Death Blow 3, Renewal 3, Goad Cavalry.

Olwen: Dire Thunder, Reposition, Glimmer, Life and Death 2, Hone Cavalry.

Do note that Olwen must have a +ATK IV. Any other IVs except for -ATK will require LAD 3 and Attack +1 Sacred Seal. A -ATK Olwen won't be strong enough in taking Clarrise down. LAD 1 should be enough, though LAD 2 should be used regardless.

Cecilia: Gronnblade, Draw Back, Glacies, Attack +2, Escape Route 3, Hone Cavalry.

A -ATK Cecilia should only be used as a 5 star. Otherwise, a 4 star Cecilia should suffice.

Strategy:

Turn 2: Place Xander on the range of the dagger user, Camus on the most southwestern spot on the map, Olwen next to Camus, and Cecilia next to Olwen

On Enemy Phase, the dagger user and green tome cavalry will attack Xander. Xander should be bulky enough to survive and kill the green tome user.

Turn 3:

The wall should have crumbled by the enemy's attack. Use Olwen to ORKO Clarrise. Provided you used the proper Olwen, Clarrise should die without having a chance to counter. However, Olwen must get Goad Cavalry to ORKO Clarrise. Without Goad Cavalry, she would die upon the retaliation strike. Before attacking Clarrise, move Camus next to Xander. After killing Clarrise, reposition Olwen to the right with Xander. After this is done, Drag Xander back with Cecilia. This is done to get Xander out of the blue tome user's range.

On Enemy Phase, Camus will be hit by the sword cavalier. Camus will kill him upon retaliation strike.

Turn 4:

Attack the blue tome user with Xander. Retribution should be active, leaving the blue tome user at 19 HP. Cecilia should deal just ENOUGH damage if she is a neutral ATK 4 star. Immediately reposition Cecilia to the right with Olwen. Use Camus' Ardent Sacrifice on Xander.

On Enemy Phase, the dagger user will attack Camus, whereas the Infernal exclusive sword user will attack Xander.

Turn 5:

Move Xander out of the way. Move Camus in and proceed to kill the dagger user. Lastly, use Olwen to finish the sword user.

Clarrise is now added to your collection of Heroes.

Ike has QR3, Ephraim has reposition, Robin has bowbreaker 1, and julia has btomebreaker

Xander is the MVP for this map.
Xander inherited Swordbreaker and Hone Cavalry (both are not necessary) and should have Reposition to retreat quickly.
Reinhardt inherited Death Blow 2 and he really need this, period!
Camus inherited Swap and Clarine inherited Fortify Cavalry which is highly recommended.

Xander must conquer the defensive tile immediately after receiving Fortify Cavalry and attack the sword cavalier. Camus should be 2-space under Xander to goad him without being at risk.
In the first Enemy phase, everyone will proceed to attack Xander, Clarisse would be damaged considerably and both cavaliers committed suicide.
Next turn, Reinhardt can OHKO Clarisse and Xander MUST retreat and reposition Reinhardt to avoid the nasty Blue mage who can OHKO, if he is damaged Clarine can heal him to nearly full health.
Camus should be fine to take out ninja and blue mage, Reinhardt can OHKO sword fighter, but be aware of Panic Ploy from the sword because the team depends on Cavalry buffs.

5* Xander (Fury/Desp/Ward Cav.)
5* Cecilia (Triang./G.tomebreaker/Hone Cav.)
5* Abel (Hp/Swordbreaker/fortify cav)
4* Priscilla (whatever)

The idea is to break the ruin, and move xander on a defensive tile, meanwhile moving Cecilia to the wall, so that clarisse can attack her, dealing almost no damage, while recieving metric tonns of it to her own face.
Move Abel near Cecilia so that she is protected from the red infantery (infernal), and make sure to stay hydrated while enjoying the carnage, and occasionaly healing Xander.

Enjoy!^^