Sunspot Lantern (Patreon)

Wondrous item, very rare

While lit, this bullseye lantern burns for 1 hour on 1 pint of oil, shedding bright light in a 60-foot cone and dim light for an additional 60 feet. The bright light is sunlight.

Sunbeam. You can use an action to speak the lantern's command word to cast the sunbeam spell from it (save DC 15), provided that the lantern is lit. This version of the spell doesn't require you to concentrate on it, but ends immediately after creating the line of radiance each time you cast it. This property of the lantern can be used three times. It regains all expended uses daily at dawn. If you expend its last use, roll a d20. On a 1, the lantern explodes, destroying itself in a burst of light. Each creature within 10 feet of the lantern that's not behind total cover must make a DC 15 Constitution saving throw, taking 4d10 radiant damage on a failed save, or half as much damage on a successful one.

Here comes the sun...