**mild act 1 spoilers** When I tried to go through mountain pass it says I was too low level so I read online I should complete the underdark.. The Underdark holds BG3's best Act 1 loot — Mourning Frost, Adamantine Forge items — but only if you visit before the Mountain Pass and follow the right sequence.
I did both act 1 areas but ultimately went to act 2 via die Underdark route for my good run. The path after the Mountain Pass seemed more fitting for an evil run to me, though you can absolutely do it as a good Tav, too. Both paths, once you enter act 2, are about equal in length until they meet up again. It honestly doesn't make a huge difference.. Baldur's Gate 3 asks you to choose between The Mountain Pass or the Underdark in act 1. Here's the best route to Moonrise Towers.