Legend of Heroes: Trails Through Daybreak - Wombo Combo
This is in the Lower Remnant Zone. For a good portion of the game, this one eluded me, but while fighting my way to the boss, I found a group of enemies that had the right amount of bulk to resist immediate death.
I had Van and Aaron use wind magic to generate hits, with neither running magic boosting anything and not boosting as I am looking to draw out the fight. I swapped Agnes out for Aaron to get the Swapper. Then I also had Bergard spamming items to get Bag of Tricks. From there, I just needed to get the seven sequential turns, avoid damage, use a charged hit, and connect an Excel Craft. Triple shard skills and triple stun helped pad my numbers.
I don't think I am going to bother with the 5x one as it seems like it will just be more trouble than it is worth.