AKA, vampirism! He looks preternaturally young (about mid-20s) despite his ancient life, and will more or less always retain his appearance from when he'd been turned. He has accelerated healing, as well as strength, speed, agility, and reflexes beyond the mortal capacity; for example, he will at times use his speed in combination with his mind powers ( see below ) to make it seem as though he has stopped time for everyone else except himself and a select person (or group of people).

He can only nourish himself on human or animal blood, as regular food can no longer sustain him. As a vampire, he does also still possess blood, which is drinkable to other vampires in small quantities.¹  If a vampire doesn't feed or otherwise allows their health degrade, their appearance will gradually deteriorate— dry, cracked skin, greasy hair, visible veins, etc.

Being a vampire also gives him a vaguely uncanny appearance: fangs, sharp fingernails, and bright amber eyes, and he is otherwise immortal save for death by decapitation, fire, or starvation.

Armand is a powerful telepath who can read and control minds, as well as communicate telepathically with other vampires,²  and he is very skilled with shielding his own mind from being read or interfered with. He can create illusions, move and/or manipulate things telekinetically, hold people within a thrall of what is essentially hypnosis, as well as implant, erase, or otherwise manipulate their memories.

The power to confuse, beguile, and otherwise "spellbind" humans and/or other vampires. It requires eye contact and a deliberate intent to persuade the victim of the reality the vampire wants them to believe, but via misleading and confusion, not mind control or enslavement.

He can create fires telekinetically, either remotely (causing something or someone to explode in flames) or else manually.

Armand can fly! Well, float? Same difference either way.