[quote=Roose Hurro]
I have another twist on the binary idea... a Dyson Sphere around the companion star, the whole construct circling the primary of the pair. Huge, huge amount of space, enough to "house" thousands of civilizations at once. If not tens of thousands... or more. Actually created this for an idea of my own, but...Oops, almost forgot: This Dyson Sphere is habitable both on the inside and the outside surface. Like I said, HUGE huge surface area to play with.
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And in the centre of this 'Dyson Sphere', there would a large, uninhabitable central star, almost like our sun.
Perhaps, if magic is going to play a role in this, magic tendrils that are invisible to the naked eye come out of this central star will connect to some planets, causing them to have magic, while the untouched worlds don't.