Avian Of Orcus

Dive Attack. If the Avian is flying and dives at least 30 feet straight toward a target and then hits it with a melee attack, the attack deals an extra 6 (1d10) damage to the target.

Strength Of The Flu. Whenever the Avian is within 10 feet of someone afflicted by the Orcus's Avian Flu, they gain 5 hit points at the start of their turn. 

Talons. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 9 (1d12 + 3) slashing damage. 

Beak. Melee Weapon Attack: +2 to hit, reach 5 ft., one target. Hit: 11 (1d12 + 4) piercing damage. 

Orcus's Avian Flu (1/day). The Avian Of Orcus uses its talons to latch on to a victim, then opens its mouth abnormally wide, disconnecting joints. Seeming to come down from where the brain is located, a light green gas expels outwards from the open mouth, onto the victims face. The victim must make a Constitution 13 saving throw. On a success, it has advantage on the next roll against this ability within the next 24 hours. On a failure, the victim contracts an Avian Flu. Against any type of creature that is not Avian, they simply get the poisoned condition until lesser restoration or a similar spell of a higher power is cast on them. On any Avian creature, the effects are worse. Due to the nature of the flu and the biology of the creature, it affects them worse. They get the poisoned condition, and it cannot be cured by lesser restoration. After two days of having the flu, the creature begins to develop a nasty cough and horribly aching muscles. After another day, the creature begins to have a terrible headache, giving them disadvantage on concentration checks and any checks against something that would mess with their mind. After a fourth day, the creature's movement speed becomes reduced by 10, and their skin begins to decay. On the fifth day, the creature dies, and their body decays abnormally fast. After 1d4 + 1 hours of death, they are reborn as an Avian Of Orcus. At any point over the four day span, a spell of greater restoration, or a similar spell of a higher power, can end this process and undo the effects. If the target is revived after the five day point, they still become an Avian Of Orcus, the process simply happens quicker.