Unicorn

Regional Effects

Source: Monster Manual

Transformed by the creature’s celestial presence, the domain of a unicorn might include any of the following magical effects:

• Open flames of a non magical nature are extinguished within the unicorn’s domain. Torches and campfires refuse to burn, but closed lanterns are unaffected.
• Creatures native to the unicorn’s domain have an easier time hiding; they have advantage on all Dexterity (Stealth) checks made to hide.
• When a good-aligned creature casts a spell or uses a magical effect that causes another good-aligned creature to regain hit points, the target regains the maximum number of hit points possible for the spell or effect.
• Curses affecting any good-aligned creature are suppressed.

If the unicorn dies, these effects end immediately.