Answer:
Always wax, yet always wane: I melt, succumbed to the flame. Lighting darkness, with fate unblest, I soon devolve to shapeless mess.
This thing runs but cannot walk, sometimes sings but never talks. Lacks arms, has handsอพ lacks a head but has a face.
The more of it there is, the less you see.
What goes in the water black and comes out red?
I fly through the air on small feathered wings, seeking out life and destroying all things.
If itโs information you seek, come and see me. If itโs pairs of letters you need, I have consecutively three. What am I?