To summarize what the AU is about, basically different events occur that cause certain events and characters to go and act differently than we know them. In this version of Equestria, it is ruled by the Pillars of Equestria (Starswirl, Mistmane, Rockhoof, Somnambula, Flash Magnus, And Mage Meadowbrook) who are cursed to be immortal.
 
Sunburst is Starswirl’s apprentice when it comes to magic, he has a fascination on experimenting on magic spells and trying to create new spells. He’s shy and not much of a social guy, but all of that changed when Starswirl sent Sunburst to Ponyvile to learn about friendship. The longer he stays in Ponyvile with his new friends, the better pony he becomes, but when Equestria is in danger, he leads the way to victory while possessing the Element of Magic.
 
(and no, he does not turn into an alicorn, Starswirl doesn’t know that spell)