Since we are on the topic of Reed's ridiculously impressive mind, this feat definitely needs to be mentioned here...
After recreating the entirety of Marvel from scratch, the Alien Entity came to the realization that he/it could not hold it all together by himself; he did not possess enough knowledge... But Reed did. That said, the AE went on to utilize Reed's mind as the blueprint, the glue, through which ALL of Marvel was shaped and subsequently held together: