Long ago, in Equestria during the end years of the Changeling war, six humans appeared, and they helped using bows, swords, and even some guns and cannons! The weapons were specially granted to them, others already had them, there timelines were really split apart. But the six helped end the war, but before there work was over, Discord showed up with his chaos made army, but was defeated at the final battle by the six humans before they left Equestria and went on to live there lives.

Years later. Six friends, the descendents of the six humans. Stubble apon an old room and find many different items with there last names on it, they get confused and even more when the door closes behind them. Then a portal opens and drags them in with them. Once they are they don't get the welcome wagon they were expecting, especially when it's six multicoloured ponies with wings and horns who attack them. And try to capture them, only one thing to do, run!

But once no hostility is established, the princesses wish to see and show them, once they do, the six will have to take a dive to the heart to find there ultimate weapon.

Yeah, kinda of a kingdom hearts crossover.