The Office Behind the Door

I would assign one unit to 2 or 3 enemies, with those enemies specifically in mind. For example, I was having a tough time clearing only because of the red cavalry unit, so I trained the 3 star Ursula to 4 stars, then used her to clear the 4 star map, since she has weapon advantage and anti cavalry. Cecilia is good for 4 of the 5 units on the map, including the green armor. You really have to take her to 40, though. Level up your castle and use crystals if you have to. Also, I switched from Serra to Lissa once I found out Rehabilitate easily heals 40+ HP, freeing up Olivia to Dance for offensive players. Also, I recommend you have someone who can take 2 or 3 hits, since right now there’s nothing stopping the red cavalry from ripping through your team, which is made entirely of backline units.

Hmmm. Tiki can take the Red Cavalry and the Green armor, but the problem is that the red cavalry will advance with Ursula, except for a single turn in which their range of attack differs. A FRobin Cecilia Lissa Tiki team might work... Cecilia should lure in the thieves and take them out ASAP, then pull back before the armor and cavalry move in. Robin should engage Ursula in the space no other melee unit can reach her, then pull back. After that, Tiki can mop up with ease. Lissa is there mainly to heal Cecilia. What I don't like about using Setsuna here is that she counts as infantry, and basically will sit out the rest of the match after the assassins. At least Cecilia can help with the armor and Ursula in a pinch. If Cecilia isn't hitting hard enough, I would swap in Olivia instead of Robin, and chance Ursula with Cecilia despite the anti cavalry. As long as she survives a little bit, Lissa will guarantee full health.

I would assign one unit to 2 or 3 enemies, with those enemies specifically in mind. For example, I was having a tough time clearing only because of the red cavalry unit, so I trained the 3 star Ursula to 4 stars, then used her to clear the 4 star map, since she has weapon advantage and anti cavalry. Cecilia is good for 4 of the 5 units on the map, including the green armor. You really have to take her to 40, though. Level up your castle and use crystals if you have to. Also, I switched from Serra to Lissa once I found out Rehabilitate easily heals 40+ HP, freeing up Olivia to Dance for offensive players. Also, I recommend you have someone who can take 2 or 3 hits, since right now there's nothing stopping the red cavalry from ripping through your team, which is made entirely of backline units.