Lumin
tiny celestial, neutral good
Emitter: The lumin sheds bright light within 15 feet, and dim light for another 15 feet.
Unusual Nature: The lumin does not need to eat, breathe, or sleep.
Magic Resistance: The lumin has advantage on saving throws against spells and other magical effetcs.
Actions
Radiant Pulse: Ranged spell attack: +4 to hit, range 30ft, one target. Hit: 4 (1d4+2) radiant damage.
Invisibility: The lumin magically turns invisible, temporarily suppressing its light, until it attacks or until its concentration ends.
A lumin is a minor celestial that appears as a sentient glimmer of light. Earning the trust of a lumin is hard, but once gained, their loyalty is very strong. Sometimes lumins live in hallowed places, forming small swarms that protect their abode from intruders.
The Find Familiar spell can summon a lumin.