Beli

Arctic Hunter. The beli has advantage on Dexterity (Stealth) checks made to hide in snowy terrain. In addition, it has advantage on Wisdom (Perception) checks that rely on sight in snowy terrain.

Cold Regeneration. If it starts its turn in an area with below freezing temperature, the beli regains 3 hp. If the beli takes fire damage, this trait doesn't function at the start of the beli's next turn. The beli dies only if it starts its turn with 0 hp and it doesn't regenerate.

Flyby. The beli doesn't provoke opportunity attacks when it flies out of an enemy's reach.

Ice Dagger. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 5 (1d4 + 3) piercing damage plus 5 (2d4) cold damage.

Icy Shortbow. Ranged Weapon Attack: +5 to hit, range 80/320 ft., one target. Hit: 6 (1d6 + 3) piercing damage plus 5 (2d4) cold damage, and the target must succeed on a DC 13 Constitution saving throw or suffer one level of exhaustion from the arrow's icy chill. On a success, the target can't suffer further levels of exhaustion from any beli's Icy Shortbow for 24 hours. If a creature would suffer a sixth level of exhaustion from this attack, it is reduced to 0 hp instead and must make death saving throws as normal. A creature reduced to 0 hp in this way can't suffer further levels of exhaustion from any beli's Icy Shortbow for 24 hours.

Invisibility. The beli magically turns invisible until it attacks or until its concentration ends (as if concentrating on a spell). Any equipment the beli wears or carries is invisible with it.