Towering Spear
This short spear’s haft is thick and octagonal, its long thin spire-shaped blade marked with a rune that seems to grow and shrink while watched.
I was able to confirm this auctioned item’s stated effect via experimentation: when the bearer kisses the rune they rapidly grow to double their size; the rest of their equipment does not, save for the spear. This effect lasts until the sun sets.