Valravn, The Crown of Bone

Keen Sight. The roc has advantage on Wisdom (Perception) checks that rely on sight.

Undead Fortitude. When Valraven reaches 0hp it makes a constitution saving throw of 10 with advantage. If it succeeds then it rises up with 1d20+4 hp.

True Sight. Valraven is powered by an ether crystal giving it magical vision. Valraven can see through objects and has advantage on trying to see invisible creatures.

Multiattack. The roc makes two attacks: one with its beak and one with its talons.

Beak. Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 27 (4d8 + 9) piercing damage.

Talons. Melee Weapon Attack: +13 to hit, reach 5 ft., one target. Hit: 23 (4d6 + 9) slashing damage, and the target is grappled (escape DC 19). Until this grapple ends, the target is restrained, and the roc can't use its talons on another target.

Dive. Valraven can ascend into the clouds above its nest becoming invisible in the cloud cover and spends it turn doing so. The next turn it dives through the clouds down on a specific target making either a beak or talon attack with advantage. If Val raven hits it adds 10d6 to the damage and if the target is still standing it is knocked prone. Additionally, every creature in a 20ft radius must make a dex save of 19 or be flung back 5ft and knocked prone taking 1d6 piercing damage from the bones surrounding the lair.

Chant of Illusion. Valraven comes down to ground level and focuses on one target that it can see. This target must make a wisdom saving throw of 16 as Valraven begins to telepathically chant a discordant melody in its mind giving it one of the following effects determined by a D4. If a player has already been affected by the chant and saved from it or is already under one of the chants affects then it can not be affected again.

1. The target  hears flapping of giant wings above them and sees another Valraven pierce through the clouds. Each time the target takes an attack it has a 50% chance of taking a shot at the illusion which reacts the same as Valraven would. The target can take its turn to make another wisdom saving throw to notice that the other is an illusion.

2. The target sees 4 shadowy humanoid figures rise up from the bones around him. These shadowy illusions have a +5 to hit with spear shaped shadows that do 1d6+2 psychic damage as the target feels the spears pierce through their skin without actually happening. These shadows have no hit points and can only be defeated by the target taking their turn to do an intelligence saving throw.

3. The target sees the magnificence of Valraven and accepts that it is the true god of death. The target must take its next turn to use its normal movement and walk toward Val raven after dropping its weapons and leaving itself open for Valraven's judgment, giving Valraven advantage on all attacks until the target makes a successful wisdom saving throw at the end of each of its subsequent turns.

4. The target is assaulted by the chants in its mind taking 3d12 psychic damage and becoming deaf. The target will continue to be deaf and take the psychic damage on each turn until it makes a successful wisdom saving throw.

Gust Macabre: Valraven causes a huge gust of wind and bone to shoot downward in a inverted 60ft cone. Anyone in this area must make a dex save of 17 or take 4d8 piercing damage and get thrown 10ft and knocked prone.