Item from pokemon-unova by
The dormant form of Reshiram — a smooth white stone the size of a grapefruit that wakes in the hands of the Hero of Truth.
The Light Stone is Reshiram in hibernation. It has no active powers in its dormant state — it warms faintly to a worthy presence and hums at the ear — but when the right person holds it with the right conviction, it hatches in the holder's hands into the fully active legendary dragon. Cedric Juniper has published papers attempting to measure its resonance signature; the papers are inconclusive because the stone refuses to respond to instruments.
A pearl-white ovoid stone with a subtle flame motif etched on one face, warm to the touch, giving off a faint humming note that only becomes audible within a few feet. Sits on a black iron stand at the summit of Dragonspiral Tower.