So I've completed good and evil Tav and an evil Durge and in act 3 on my good Durge, but with ACT 3 rather messed up at the moment it's been a slog. My evil Tav was more selfish than evil. I started out as a Paladin, accidentally broke my oath a few minutes after crash landing and decided to embrace it(I was planning a good run for my first). So while I destroyed the grove, I saved or killed people as i felt like the rest of that playthrough. It made it rather weird to be honest, but I made my decisions on what was best for me in the moment. So the Last Light survived for my own reasons, not much else did.