Making a very special number out of primes.

It's a gold level Hypernion!

Try this interactive sudoku-esque puzzle, kindly provided by Muddled Puzzles!

Katastrophion is a level up from Logikion — if you like sudoku, you'll like this!

Logikion is a level up from Pandemonion, one of our new interactive sudoku-like puzzles!

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