Anahera the Storm Hunter

Ambusher. The hunter has advantage on attack rolls against any creature she has surprised.

Archer's Eye. As a bonus action, the hunter can add 1d10 to its next attack or damage roll with a longbow or shortbow.

Doppelganger Ancestry. The hunter has advantage on saving throws against being charmed, and magic can’t put her to sleep.

Steel Will. The Hunter has advantage on saving throws against becoming Frightened.

Colossus Slayer. When the hunter hits a creature with a weapon attack, the creature takes an extra 1d8 damage if it’s below its hit point maximum. She can deal this extra damage only once per turn.

Spellcasting. Anahera is a 12th-level spellcaster. Her spellcasting ability is Wisdom (spell save DC 14, +6 to hit with spell attacks). The hunter has the following ranger spells prepared:

1st level (4 slots): jump, hunters mark, ensnaring strike, hail of thorns
2nd level (3 slots): enhance ability, locate object, silence
3rd level (3 slots): lightning arrow, conjure barrage, elemental weapon

Multiattack. Anahera makes two melee attacks or two ranged attacks.

Glaive of Storms. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 11 (1d10 + 5) slashing damage plus 7 (2d6) lightning damage and the target must make a DC 14 strength saving throw or be pushed back 5 feet.

Longbow. Ranged Weapon Attack: +9 to hit, ranged 150/600 ft., one target. Hit: 10 (1d8 + 5) piercing damage.

Shapechanger. As an action, the hunter can shapechange into a medium or smaller humanoid it has seen, or back into its true form. Any equipment it is wearing isn't transformed. If the changeling dies, it reverts to its true form.