What does it mean when spheres are opposed? Does it mean they're mutually exclusive and that taking a trait in 1 tree locks the other one out? This is what I guess it does, but I couldn't find the explanation.
Further small note: Fire doesn't seem to have a noted opposed sphere (should be water, as that one has fire noted as opposed?)
And the primal sphere doesn't seem to have a benefit for having all your 'sphere traits' be primal traits. Is this intentional because they're stronger than the others?