Your Troop comes upon a wall of ice. From within, you can hall hear snickering, the jargon of realtors and the constant chanting of "Location, Location, Location." This must be the place. Destroy the wall to proceed.
The first act of this raid, Frozen out consists of a single Water target, a wall of ice.
Since the Ice Wall is a single target, Using 3 Leaf combos is the most effective way to do damage. Leaf monsters excel in this entire raid as all of the monsters are of Water type. Fire is weak to Water type, so doing a 3 Fire combo is the least useful of the Elements combos.