We're not supposed to mention the breeding or battle calculator because it is not put out by Storm8 the game creators.
That said, you should absolutely visit the site to use for help. Regular people contribute to this site, so in this case the dragon breeding because it's a new one hasn't been added. You can breed the dragon using red & yellow or royal & yellow. There are many combos within these pairings that will work. I used a Royal/diamond dragon with a Royal/yellow dragon and got it. Google dragon story breeding calculator, you want the wiki Fandom site. It also has a battle calculator to help choose a dragon for the arena. Lots more info too. Link below is copy pasted but missing "dragon" before story. If you need help I'm here or you can PM another player. If you post about it, the mod will likely remove it. Good luck!