Sphere of Light

The Ball of Light (光の円, Hikari no Maru) is an important magical item in the original Dragon Quest and Dragon Quest III.
As Dragon Quest opens, the Dragonlord, the game's primary antagonist, kidnaps Princess Gwaelin and steals the Orb, allowing him to unleash monsters and other horror on Alefgard.
In Dragon Quest III, it is obtained from the Dragon Queen and is instrumental in defeating Zoma.