Well, maybe they helped out or inspired the Egyptians to build one themselves, because what you actually see in Egypt is an evolution of pyramid shapes over a long period of time. That means—they, too, figured out through “trial and error” what the angle of inclination needs to be to achieve a stable pyramid shape. If aliens had been directly involved in the construction, you’d have to assume they knew what they were doing, right? 

In any case, here’s a watercolor illustration for my children’s book about ancient Egypt that shows the evolution of pyramid shapes. So we also have step pyramids and a pyramid that’s bent because, halfway through construction, they realized the angle was too steep. And to save the structure, the angle was quickly adjusted right in the middle. 

Below you can see Sneferu’s Red Pyramid. For anyone who’s been there: you can go inside, but you actually have to go DOWN—and you have to waddle like a duck. You’ll never experience muscle soreness like that again in your life. 😂