I think that the whole "use a fourth color to seal the rifts" plan, while probably having some relevance to the final conclusion, will not ultimately *be* the method by which that conclusion is obtained. There's still the whole bit about the world inside the rifts. Rich wouldn't have bothered to put that in the story if it wasn't going to have relevance. So any plot that is just RC agreeing with Thor's plan can't be the full story since it would just seal off that world with no explanation as to what it is or why it's there. The plan as it is doesn't even allow for any exploration of that at all.
No clue how exactly that's going to play out, but it won't be as straightforward as that.
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King Nobby wrote:
More words please