Glasslark

These birds aren't truly made of glass, but their feathers are so reflective that they mirror the world around them. This effect makes these birds very difficult to see, but if you spot a strange warping of scenery nearby, it may be a glasslark hopping from branch to branch.

Glasslarks are known to perform murmurations when they join together in big flocks. The large numbers of ultra-reflective birds flying in synchronized aerial displays takes on the appearance of a mirage. It can be difficult to discern what you are seeing, as the flock will just appear as a shimmering, warping band of light and shadow in the sky.

Finding a glasslark feather is considered to be good luck, though it's frowned upon to poach these creatures for their feathers. Only discarded feathers should be collected. Glasslark feathers are popular additions to fishing lures, as the highly reflective surface is attractive to fish.