So, could the God Slayers have been made to fight the Dragon Slayers? Unlikely since the dragons against the DS were against coexistance with humans, but where else could they have come from? This is my big question for now, as it kinda seems like they just come from no where or were just invented by some other powerful mage to mimic ds.
PS: Odd thought, what if Zeref's demons (Deliora, the Spirit of the Flute, etc) were actually created to help defeat Acknologia? Wasn't Zeref acting afraid of AL? Maybe I'm just remembering inaccutely. Don't feel like looking it up.