Quote Originally Posted by TheDecay View Post
Have YOU beaten the final boss? Ultima did NOT cause the blight. He escaped from the blight and he literally told Clive the same fate will come to Valisthea. The Blight is quite literally STILL a mystery.
He straight up explains that magic was the direct cause of the blight and the crystals accelerated it... It's why Clive did what he did at the end of the game and why life on the planet is completely restored in the post credit cutscene. Magic no longer existed, thus the blight went away.

There is no mystery, you just didn't pay attention.