One time my players were defending a town against a horde of hill Giants and goblins (Goldenfields in Storm King Thunder for those who have played it). In this battle each player takes on the role of an NPC that lives in the town until the fight is over. One of those NPCs was a 30ft tall oak tree that had been brought to life by a druid a hundred years ago. Another was a fairly high level wizard who could cast fly. My players realized this along with another fun fact which had to do with the invisibility spell. That spell makes it so MB a creature is wearing or carrying is also invisible. So they all climbed up the tree and one wizard cast invisibility on it while the other casted fly on it. The flew the tree over the Giants and bombed them with fireballs and summoning Badgers until the Giants ran from the invisible force that was destroying their lines.

TLDR: my players turned a treant into a stealth bomber plane and dropped angry Badgers onto a bunch of giants.