Another run where the prestige class did nothing. No matter what I can't see a world where the mirrors it spawns does anything noteworthy. Since they spawn on standstill you can't make enough of them to do any meaningful damage; also they are limited to a range of 4 from the player making them even worse.
Otherwise it's a "aggressively stand still" build. Since Agara trigger stand still effects on prayers and Crystalform also trigger on prayer it steadily scales my damage. Crow Visage did Crow Visage things.
Even then I feel like I won mostly because I never got screwed by mapgen. Got a really favourable map against the final boss where I slowed him down to a crawl causing him to be too busy killing mirrors to be able to reach me. Didn't even see him once.