As a member of the Judu Des Clan that had been dubed heroes for defeating evil dragons and mythical creatures, Pred had a tough childhood from extremely rough parents. At first, he didn't understand all of the mythic beast hate, even after being exposed to the lores of the Great Equestrian Fear War and other Mythic Beast horror stories. But when he was in high school, Pred fell in love with a popular mare cheerleader named Mara Kindness who was very forgiving and understanding and extremely kind despite being popular, and is the only mare not attracted to a mean and stubborn dragon jock named Champion Light, who tried all he could to make Pred extremely unpopular just for the sake of establishing social order. He even goes as far as exposing Pred's lineage to Dred Judu Des. But Mara always prevented this by reminding everyone the importance of tolerance and forgiveness and that it was such things that prevented everyone from being frozen to death by Windigoes. As a result, Champion became unpopular to everyone, even other mythic beasts and dragons and those who were his friends, leading to Pred becoming the kid on campus.
While Pred enjoyed his praise and had started considering the beliefs that his clan had were not all true, and even earned the heart of Mara, things got dark for him when he saw Mara kissing Champion, leaving his heart to be broken, unaware that it was a trick that Champion set up after using recently-learned dark magic to charm Mara into participating. Champion went further into his greed and corruption by planning to become the school womanizer and corrupted every mare and female mythic beast to become his harem, and to break the hearts of every colt and male mythic beast so he can laugh at their faces and established himself as the ruling jock forever in this school. Pred had started thinking that his family was right all along, and cut off Champion's middle finger after he gave him the finger, getting him to shout out his entire plan in front of everyone after a fight, and killing him by stabbing him in the heart. While this made him a hero to the students, the faculty, including Celestia who was dropping by, were not as forgiving despite knowing that Champion was committing horrible deeds. He was expelled as a result, leaving the betrayed Pred to finally acknowledge his lineage, giving him his cutie mark.
Hate for Non-Pony Creatures
Years later, with Pred being a successful warrior who had been saving lives from 'evil mythic beasts', sometimes they are legitimately evil, sometimes not, and even earning the acknowledgement of the Unicorn Council, he failed to realize that Champion Light was not just a corrupt dragon, but he was actually the nephew of an even worse dragon named Malevolent Flames, who swore vengeance on Pred and his family for the murder of his nephew, even if it meant that others had to die. Pred had then on began to protect his race from him and other corrupt creatures, and through it made friends with Grudgesly, the grandfather of Fluttershy, because of his acknowledgement that dragons were vicious creatures. Pred was there to witness the birth of Fluttershy later on, and Grudgesly's influence eventually became responsible for Fluttershy's fear of dragons, reminding Pred of a younger version of Mara.
However, 2 years later, Malevolent Flames had caused more trouble than ever. He ended up burning down an orphanage and attacking 3 small pegasi sisters, whom prior lost their parents to him. Years later, Malevolent Flames went too far this time, especially when prior to this, he murdered the parents of Hidden Shadow, and because they were related to one of the Unicorn Councilors, Flames was finally put on trial for his actions. Hostility erupted in the court room, and when Malevolent Flames intended to attack Celestia for being tough, Pred went in and killed him by stabbing him in the heart. From then on, Celestia had been trying to show Pred and the Council that not all dragons and non-pony creatures were evil, with little success. It helped little that Celestia has also been given plague for the Unity of Equestrians and Mythic Creatures, of which the Unity existed since the Fear Wars, and that there's legitimate concerns that it's not completely perfect, especially concerning Flames. This resulted in Pred becoming even more stressful since, because of the Unity, he is considered 'unneeded' and had a questionable reputation that he blamed on the Unity and not the 'innocents' he killed in accusing them of being corrupt. This reduced Pred into murderous attacks that the Unicorn Council fully accepts thanks to their leader having a past just as dark as his. Pred has been doing this even to this day, and while the Unity could do so much for so many years, it will eventually be realized that it was just too flawwed in thanks of dishonest souls in the mythic beast community and must come to an end.