Izek's Redemption Block
In my game, Izek was spared by the party and was possessed by an evil spirit to make him the way he was in Vallaki. His obsession with Ireena was one of familial love, but he didn't know the nature of his obsession with her until it was brought out in the story.
After the spirit was exorcized, it took his flaming arm with it, and he escaped Vallaki and gave himself a new name to separate himself from his past. Strahd had captured Ireena after this and, while he didn't follow the party, made his own path to try and rescue his sister.
I made him the chosen of Kavan and obtain the blood spear (as my party ignored it) and homebrewed the followers of Kavan to be another tribe of werebear lycanthropes who lived on Mount Ghakis. Following leads from a certain male dusk elf about a temple in the mountains set off to find answers on how to bring down the dark lord.
He and his followers will be found in the Amber Temple near the entrance where the barbarians led by the Gladiator will be instead. Wounded by the Flameskulls and resting, they will aid the party in their fight against Strahd, giving the party a safe place to be in the Temple and give insights into the traps ahead if they play nice as Izek, now with the new name of Vladimir, will recognize them as the people who freed him from the spirit controlling him.
I wanted to share the block I made for him which is a combination of Izek's block, Werebear, and Gladiator and hope it can be inspiration to others to do some awesome world building for these wonderful NPCs instead of having them be a one and done encounter, like Izek.