Reigning WWE Intercontinental Champion Dominik Mysterio has officially written history at the Worlds Collide event as he finally managed to beat El Hijo del Vikingo and capture the AAA Mega Championship. He has become the first Mysterio to hold two titles simultaneously.Dirty Dom winning the second title on WWE's partner brand has shaken the entire timeline and changed the trajectory of World Wrestling Entertainment, given that Dominik holds one of the most prestigious titles on RAW.In this listicle, we examine three reasons why Dominik Mysterio has become a double champion in WWE and AAA:#3. Putting Dirty Dom over as the next big starDominik's sudden rise in the Stamford-based promotion needs to be studied over the years he evolved from a lower-card rookie to one of the hottest attractions.Dirty Dom climbed the ladder of success after turning heel on his own father and joining The Judgment Day and has never looked back, ever, and continues to grow. The 28-year-old star is also a complete company man as he competes almost every week, at house shows, and PLEs, making him one of the upcoming big stars.Putting an AAA title on him, making Dirty Dom a double champion, elevates Dominik Mysterio's stardom, establishing him as the next big thing.#2. WWE Judgment Day break-upFinn Balor appears a bit jealous of Dominik Mysterio's sudden growth, as he feels he was robbed when Dirty Dom was added to the IC Title match at WrestleMania and pinned him, which has surely changed his fate.Moreover, Balor is also irritated by Dirty Dom's closeness to El Grande Americano and his spending his time with him instead of being in The Judgment Day clubhouse, where he should be making game plans.#1. Setting up mega-boutWWE Hall of Famer Rey Mysterio has been away from action since the night before WrestleMania 41, as he sustained a serious injury during a match, which has unfortunately kept him away.Tonight at Worlds Collide, the Master of the 619 was seen swinging chairs at Judgment Day, but El Grande Americano helped Dominik seal the big win. Meanwhile, as per the backstage promise made by Rey, he wrapped the title around his son's waist, who disrespected him even then.This may lead to Rey Mysterio finally returning to build a rematch against his son. This potential feud could end with a career vs. title match.