Nobody knows how much a rainbow weighs, but it's...

I am a nightmare stitched from three, A walking, breathing tapestry. A lion's roar, a serpent's bite, A goat's head staring in the night. Born of myth and breathing flame, Can you guess my ancient name?

I am giant, gray, and slow of tread, with tusks of ivory thrust ahead. My nose does work most hands would do, strong yet careful, clever too.

I creep in without footsteps, yet I swallow every path. I silence colors one by one - until only whispers remain.

This is best for taking care of your teeth or hair, maybe not both simultaneously. This may imply a close encounter with death or danger or a nearby plant along a hiking trail