Argynvost

Argynvost was a silver dragon that lived in Barovia. He was the founder and leader of the Order of the Silver Dragon which took up base in his fortified mansion Argynvostholt. He took it as his duty to prevent malevolent forces from finding and entering the Amber Temple and releasing the evil power within.

He battled Strahd von Zarovich's forces and despite early victories was ultimately defeated and slain.

Some believe that Argynvost isn't at rest himself, and may one day return and bring light back into Argynvostholt, and across Barovia. Madam Eva stated that although it is not impossible, she does not foresee the silver dragon's revival.

There is a large portrait in Argynvostholt that Rahadin told Sigismund was Argynvost, and Sigismund noted that the man in he portrait was identical to Vassili van Holtz. Argynvostholt contains a draconic mausoleum for the bones and treasure of Argynvost. Rahadin suggested to Sigismund that he wanted to try return Argynvost's bones to the mausoleum in order to revive him.

History
Argynvost came to the valley in the guise of a nobleman named Lord Argynvost. The dragon didn’t lair in the valley solely because of its idyllic beauty.

Like many silver dragons, Argynvost was extraordinarily wealthy, and he was comfortable living among humans while disguised as one of them. He used his resources to attract other champions of good, and valorous knights flocked to the valley to join Lord Argynvost’s prestigious Order of the Silver Dragon. Only those who were initiated into the order were told of Lord Argynvost’s true nature.

Arygnvost had his knights help him build the great mansion, Argynvostholt, as bastion of nobility and light, and a place to coordinate a stand against Strahd, with the help of his field commander Vladimir Horngaard. He also knew of a place called the Amber Temple — a repository of evil power guarded by the forces of good. He wanted to make sure that whatever was trapped inside the Amber Temple wouldn’t be allowed to escape, so he built Argynvostholt close by.

The mansion was destroyed by Strahd, who personally led his forces in a climatic battle with the Order of the Dragon, and Argynvost himself. Since the dragon’s death, Argynvostholt has become a haunted ruin, a former bastion of nobility and light turned into a place of desolation and unrest.

Archwizard Khazan advised that when rallying troops in Y734 he spotted Argynvost's skull in the possession of Baba Lysaga in Berez. After defeating Baba Lysaga in battle with his companions, silver dragonborn Zrazire Caluhazan invoked Bahamut's name and was able to supernaturally raise the skull from the ground. The skull was returned to Argynvost's crypt at Argynvostholt and a beacon of protection was lit.