Well Crowley made Babalon appear, and well. Only thing that makes sense having been studying for this to work and in my own opinion on this matter, conciuos manifestation. I know of a hindu tale where this happened, difference being, the one that did it rested under the wishing tree and said I wish I had many good foods to eat. He woke up and couldn't believe his eyess, so many delishious foods had appeared. Same would be with entities envision and thy'll be there. We can create in other words and make them appear through concious manifestation. I don't know if I'm correct in my thought about some of Thelema.
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From @uglyduckly