[Amechra]

Give me a bit, but I think I can crunch out a Gold/Mercury generator that turns light into cold that will be large enough to snuff out the sun.

EDIT: Get to generating Simulacra, bub; you'll need 95,046,582,003,269,947,090,587,000
Preparations to make a generator that will put out the sun.

Of course, that is assuming that you need to off it in one go...

Or we could just make a large enough Black Kaleidomantic barrier; light is information, and thus would be blocked.