The Grand Plan.

These are all terribly unlikely things that no one thought was possible. At the very least, if anyone had done it, they certainly didn't mention it to anyone else. It is why no one will sell how to make contact with Cosmic sources. If they can do that, they will be able to become usurpers. So what can a world god offer an Usurper for their knowledge? 

The answer is nothing. But the first sage found a way. That's why he gave Legion enough information about the fusion of the Tyrants so that they would covet its product and interfere in Monarch High Heaven's plan. Then he swooped in to rip off the then realm lord of information about Cosmic sources.

It is all part of his grand plan. It is not a perfect plan. He is currently struggling with a crucial step of the plan, and he can see that there will be others who will interfere with him.