Amber Shard (The Dragon’s Bulwark)

A fragment of amber that looks less like a gem and more like a splinter of solidified, fossilized sunlight trapped in iron. It is unnaturally cold to the touch. 

Feature: Dragon’s Wing: As a reaction when an ally within 15 feet of you takes damage, you project a spectral, amber-tinted wing of draconic energy. The ally takes half damage, and you take the remaining half as temporary hit points. While you have these temporary hit points, you gain a +2 bonus to AC.