The issue is not that there isn't a "fair" path to the forge...
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Let's say Lae'zel uses her psionic jump ability. Finds a waypoint. Then the other characters can teleport through the Netherese waypoints.
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You jump into the hole in the Matriarch's spider pit, for instance, and find yourself in the underdark. You can't technically climb out, but you can fast travel to an earlier waypoint.
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Why is it different ? It's exactly the same to me.
A convenient magical runes that allow you to go where you want and when you want even if there are no pathes (or if you haven't found one yet).
If they can teleport through the Netherese waypoint to the forge, why couldn't they to the surface or anywhere else ?
Don't get me wrong, I agree that we probably shouldn't be able to teleport so easily to the surface when we're in the underdark. But in my opinion it doesn't make more sense that we teleport to cross walls / lava / obstacles.
