Terrifying twins

These twins are amazingly powerful. I won't try to convince you, answer their call and find out for yourself. They hold the keys to the abyss and who goes in and out. They control the moon an the phases it goes through. They can change the fate of anyone they choose. They usually change it for the bad however, especially if they have pissed them off. I won't try to convince you of their power. Or of the fact that they do have the keys to the abyss, answer them and find out how dangerous they are.