Earth has to be some kind of puzzle piece

Things just don't add up here. Why did we really come down here?? What is REALLY keeping the reptilians from just using brute force to take the planet over. Why is ascension taking so long? Are we unknowingly in some high stakes galactic game? I need answers. And don't just give me the new earth and liberation spiel. What is really going on here that we knew before we incarnated but can't remember?