While telling tales in Curse Of Strahd, he met another group from the Material Realm, The Pack. The Pack eventually found out his secret, and got to know him, developing the nickname "Ricky" for him, which he hated. He was initially wary of these strangers, but they convinced him of their importance by telling them of their Tarokka Deck reading indicating that they were fated allies. Though unwilling to leave the base that he had spent so much time creating, he agreed to join them on a quest within the town; they had to find the missing bones of Lugdana Andral and reconsecrate Saint Andral's Church.
After the mission went awry and brought Strahd to the town, van Richten cursed their inexperience and fled, but left a note telling them to find him in Khazan's Tower if they were able to recover one of the fated artifacts. There, he learned more about Orlev ben Khazan, as well as mention of the Order of the Silver Dragon, and went on many trips to find more information. On one of these trips he was ambushed by a Werewolf pack lead by Kiril Stoyanovich, who killed Drusilla and left him near-dead.
Rudolph ran for the tower, where The Pack were waiting for him, having found the Tome of Strahd. They dispatched his pursuers, and he agreed to rejoin the group, not knowing they had learned some of his intimate secrets by reading van Richten's Journal. However, when Rudolph found that Ezmerelda had entered Barovia and had begun traveling with the Pack, the two immediately fought. Rudolph was distraught that she would follow him on such an obviously deadly journey, believing that his curse was once again coming true, and Ezmerelda stormed off to explore Argynvostholt without him.
Dr. van Richten ingratiated himself to the group during future adventurers around Vallaki, and during the Riots Of The Blazing Sun. He provided experience and perspective and was a strong ally, though the party could never quite gel with his sense of morality. In particular, he fought with Ghalwin of the Grove, a headstrong paladin who acted with the same self-righteous assuredness as Ezmerelda, but Rudolph found more of a friend in Atlas Atruvian. The two old clerics shared similar past, and he opened up to Atlas about Erasmus and Ezmerelda.
Their journeys lead to the Riots Of The Blazing Sun, and ultimately into the mires of Berez, where disaster awaited. The party attacked Baba Lysaga in an effort to save their friend Muriel Vinshaw without knowing much of their foe, and paid their price in blood. Atlas and Shakti of the Wildhunt were killed near-immediately, and van Richten pleaded with Ghalwin to escape on Verity and use The Abbot's miracles to revive them. The paladin listened, but Rudolph was killed during their attempted escape; Ghalwin took his Ring of Mind Shielding, which contained van Richten's soul, and fled.
van Richten prepared himself as best he could, casting an offensive assault against Baba Lysaga, but was crushed under the roots of her Creeping Hut.