This is not a single-type dungeon. The enemy pool covers Bug-type, Fire-type, Grass-type, Water-type, so check the reward route and main enemy types first, then swap in Flying-type / Fire-type / Poison-type attackers.
Deal with Florawn, Clamwhirl, Flutterby first, then clean up the lower-threat enemies. Because this dungeon has multiple waves, keep at least one slot for a tank or sustain option.
Do not overbuild for only one wave if that makes the next wave counter your whole team. Both physical and special damage show up, so avoid building only one defensive side.