So here is the origin of Kraven in Hadie's Journey. During imprisonment on the Isle of the Lost, Evil Queen sought out Scar because he was royalty, but she didn't know was he was a lion before being trapped on the Isle. Evil Queen wouldn't leave Scar alone so eventually he gave into her needs so that she could leave him alone. The encounter left Evil Queen to be pregnant, Evie was excited to be an older sibling. But after Kraven was born, Scar explained his past to her and she quickly became disgusted at the fact that she gave herself up to an animal.
She lied to everyone on the Isle and said that her baby died as a stillborn, but she really left Scar to raise him (No one knew that she had a child with Scar, the only one who knew was Maleficent). Scar decided to raise his son the right way and teach him to not make the same mistakes he did. Kraven became best friends with Hadie despite being a year older than him. Kraven held deep hatred for Evil Queen and Evie growing up. When Hades pushed his son through the barrier, Kraven was eager to reunite with his friend when the barrier was opened again, even if he had to sneak through when others were being chosen.
But when the barrier was finally taken down, Kraven immediately took the chance to find Hadie. But when he couldn't find him, he fled Auradon with his father and they began hunting bad people out of the country. But once he hears about Hadie's return to Auradon, he makes it his mission to reunite with his friend.