The Hwacha (fire cart) I did for Dekogon's Medieval Times pack. The Hwacha incorporated cylinders full of gunpowder strapped to arrows. Once they were lit they flew out like rockets. One cart could be fully packed with 100 arrows.

Fully loaded comes in at 11,453 verts / 18,708 tris. Empty with only the cart at 3,251 verts / 5,540 tries.