Satan isn't the baddie

In my first 2 books, Satan was the big baddie, but then I realised that 'we' are worse than him. We are the ones who kill, maim and destroy. Satan only suggests, only makes the deals. So there's a partnership in the 3rd book of two humans, against what's 'right'. Satan is behind it all, of course, with his 'big bad deal', but the driving force is us. The humans do the actions. It's set in Atlantis, so you can work out the ending. But just how does it all get there? And where do the dolphins come in? And the Letharians? And God? And everything else? Getting to the end, just off 50,000 words ATM.