This is an idea that's been in my head for a while now.

Basically, the idea is what if these two were the reincarnations of the Champions of Light and Darkness respectively, and as such were destined to battle each other for the fate of Equestria, and the world? This would be after Tirek discovers the powers of Darkness, and becomes its champion, and our pony heroes have to help Scorpan find the power of Light. It's a trope that's been done many times before: two forces are born that are destined to war with one another, and bring forth a new world by destroying the old in their battle. Supernatural had Michael and Lucifer who were set to jumpstart the apocalypse with their battle, as was the same with Transformers when it involved Primus and Unicron, and Regular Show with Pops and Anti-Pops. Two opposing forces locked in eternal conflict for all eternity.

And the reason, in this case, is due to the reincarnation of the Champions of Light and Dark spanning through the ages.

It would have also made for a good series finale in my humble opinion. Like a play on "Rescue at Midnight Castle": Tirek discovers a powerful weapon that awakens his true self, and makes him the Dark Lord that threatens all of Equestria. But in that time, the ponies learn that his brother, Scorpan, was his counterpart destined to defeat him, and they spend much of the season helping him hone his awakened powers. But it takes more than Light to triumph over Darkness, and after a lengthly battle in the finale against Tirek's recently formed armies, and the forces of Equestria and Beyond, the Mane Seven (which includes Spike, of course), The Pillars, and The Student Six combine their powers into Scorpan to give him the power he needs to defeat Tirek for good. Perhaps even end the cycle of war the two of them are trapped in by becoming one with the ether permanently. Or Tirek himself is banished body and soul to that realm for all time to end the cycle. sigh If I had time, i'd set up a synopsis for this story. But for now, you'll have to settle on this.

Hope you all like it.

Credit for the artwork goes to MelSpyRose
Credit for the template goes to WOLFBLADE111