Aecer Guard

Keen Senses. The Aecer Guard has advantage on Wisdom (Perception) checks.

Regeneration. The Aecer Guard regains 10 hit points at the start of its turn. If the Aeiser Fenra takes acid or fire damage, this trait doesn't function at the start of their next turn. The Aeiser Fenra dies only if it starts its turn with 0 hit points and doesn't regenerate. 

Multi-attack. The Aecer Guard makes three attacks: two with its longsword and one unarmed.

Longsword. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 11 (2d6 + 4) slashing damage.

Unarmed. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 7 (1d6 + 4) bludgeoning damage.

Charge. If the Aecer Guard uses their action to Charge, they can use their bonus action to make an unarmed attack at advantage or use 10 ft of movement to push a target 10 ft in any direction they choose.

Shadowrend. As a bonus action the Aeiser can travel 300 ft. through the ethereal plane from one shadow to another as long as both are at least 5 ft. by 5 ft.

Sentinel. Aecer have mastered techniques to take advantage of every drop in any enemy's guard, gaining the following benefits: When you hit a creature with an opportunity attack, the creature's speed becomes 0

Retaliation.  When Aecer take damage from a creature within 5 feet of them, they can make one melee attack either with its longsword or an unarmed strike.