Brodin

Keen Hearing and Smell. The wolf has advantage on Wisdom (Perception) checks that rely on hearing or smell.

Pack Tactics. The wolf has advantage on an attack roll against a creature if at least one of the wolf's allies is within 5 feet of the creature and the ally isn't incapacitated.

Standing Leap. Brodin’s long jump is up to 20 feet and its high jump is up to 10 feet, with or without a running start.

LVL 3:

Living Shadow. While in dim light or darkness, melee attacks are at disadvantage and has resistance to slashing, piercing, bludgeoning, lightning, necrotic, and cold damage

Darkness. Can cast darkness innately once per long rest. At 7th level can twice.

LVL 6:

Evasion. If Brodin is subjected to an effect that allows it to make a Dex saving throw to take only half damage, it instead takes no damage if it succeeds on the saving throw, and only half damage if it fails.

Multiattack. Brodin makes two attacks with its claws.

Claws. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit:13 (4d4 + 3) slashing damage.

Bite. Melee Weapon Attack: 

LVL 3:

Arc Bolt. Range Spell Attack: reach 60ft., one target. 

Hit: 2d8 lightning damage, and lightning jumps from the target to one enemy creature of the Brodin’s choice that it can see within 20 feet of the target. That second creature must succeed on a DC 15 Dexterity saving throw or take 2d8 lightning damage. Can use once per short/long rest.

Lashing Shadows. Brodin chooses up to 2 creatures within 60 feet. Creatures must succeed on a DC 15 Dexterity saving throw or take (3d6) necrotic damage. Can use once per short/long rest.

LVL 5:

Shadow-Arc Breath. Brodin exhales shadowy arcs of lightning in a 30-foot cone. Each creature in that area must make a DC 15 Dexterity saving throw, taking 2d6 necrotic and 1d6 lightning damage on a failed save and is stunned, or half as much damage on a successful one. A humanoid reduced to 0 hit points by this damage dies and its life force melts to shadow and is absorbed by Brodin, healing him for the necrotic damage dealt.

Shadow Stealth. As a Bonus Action, while in dim light or darkness, Brodin can melt into shadow and become invisible until it attacks next.

Shadow Stride. As a bonus action, the horror can step into a shadow within 5 feet of it and magically appear in an unoccupied space within 5 feet of a second shadow that is up to 60 feet away. Both shadows must be cast by a Small or larger creature or object.

Shadow Hide. When an attacker hits with melee attack or grapples Brodin his shadowy hide damages them and deals 2d4 necrotic damage. As long as Brodin is grappled the creature takes damage at the start of each turn.  Increases by 1d4 at level 4, 8, 12, 16 and 19.

Death Shadow. When Brodin dies, he explodes. Each creature within 30 feet of it must make a DC 18 Dexterity saving throw, taking 2d8 lightning damage on a failed save, or half as much damage on a successful one. Increases by 2d8 at lvl 5, 9, 13, max of 6d8. Brodin’s spirit becomes one with shadow and retreats to Galahad until the next dusk after a 5-6 Recharge.