First, no deck image. Deck images are required in those sections.
Second, this is not a rush deck. For a "pure" rush deck, I'd use 6 Devourers, 6 Dragons, 6 Drain Life, 1 Nightfall, and the rest pillars. Well, maybe some tweaking is required, but that's generally how I'd go with a Darkness rush deck. You don't need any defenses with AI3.
But still, I'd never use Darkness at all for AI3 grinding because Darkness is not fast. I'd rather just use Shrieker spam, which is much, much faster.