The Great Emperor’s Thousand-Troop Summoning

The empire has fallen, and I've transmigrated into a destitute young prince fleeing for his life. No chance for revenge? No hope of restoring the kingdom? Holy crap... what's this? An Emperor's Growth System? It can summon heroes from the ages? It can summon millions of heavenly soldiers? It can even open portals to all kinds of planes? Is this a portal to Douluo Dalu? Hahaha! You little brats, just you wait. Once I lead millions of troops to trample everything for thousands of miles, you'll all be kneeling before me, calling me Grandpa!