Although when communicating, Vadriel uses his black hole form shown, Vadriel's most common form is a lean, tall demon with a few spikes on his shoulder. Sometimes, he will have a tail. Vadriel's color scheme varies, but it is usually either red and black, purple and black, or purple and blue. The one thing that always stays the same on every Vadriel incarnation, however, is his eyes, which are red, and his helmet, which has small horns and teeth. Beneath his helmet is a pale-skinned face with long white hair. Vadriel's true form has yet to be seen.
Vadriel, along with Omega, is the twelfth boss. He takes a humanoid form. Independently, Vadriel can use a claw attack, a beam attack, and a dive attack. He wields Death, in the form of the scythe, and whenever he swipes at the player with it and successfully damages them, he curses them and gains the amount of health he took from the player. Together, Omega and Vadriel can produce a more powerful beam attack in which Vadriel charges at the player, they can summon a swarm of bats from all sides, and they can perform the Demonic Megiddo. They both have 3000 HP each, meaning 6000 HP altogether.
Vadriel, merged with Dracula, once more attempted to conquer the world. However, he was stopped by a man named Jacen Belmont. When defeated in his normal form, Vadriel transformed into a massive version of himself. He brought Jacen to another realm with the castle floating in the background. He was defeated due to Jacen turning into a special demon form, but survived. However, as he began to grow in strength again, Jacen telekinetically hurled the castle at Vadriel. The castle impaled him, killing him once and for all. However, recently, Omega was revived, hinting that he may attempt to revive Vadriel.
Vadriel was revived eventually by Maldus. However, Maldus did not realize that Vadriel needed a host, and attempted to kill Jacen Belmont. Maldus failed, but Vadriel, in spirit form, tried to kill Jacen, once more failing. Vadriel knew that neither he nor Maldus could kill Jacen, and so, despite Maldus' protests, killed Maldus and possessed him, transforming into a massive demon. He was ultimately destoyed once more, but Omega still remains, still trying to revive him.
Vadriel was resurrected a second time by Omega and Arctus.
Vadriel is the ninth boss in Requiem of Agony. He can shoot beams, fireballs, use his sword and scythe to attack, and use his claws. He has 4315 HP, and his theme is Bizarre Room.
Vadriel is the thirteenth boss, fought alongside Omega. He has all of his attacks from Battle of Legends, and Omega, in his eye form, does all of his attacks from Battle of Legends too. He has 5000 HP, as does Omega, totaling 10,000 HP in all. If the Xbox 360 version is used, their theme is Proof of Blood. If PS3 is used, their theme is Bizarre Room.
Vadriel was killed, along with Omega, but the true power of the Vampire Killer was used to kill them. Omega went to the underworld, and used the power of the Vampire Killer to fully resurrect Vadriel.
- BEFORE BATTLE: "Well, Belmont. Thanks to you, my...our plan was successful. But now, you are useless. It is time to die."
- WHEN HIT: "Ack!"
- AFTER DEFEAT: "Impossible..."