Power for an Evocation

I’m curious: Is the meditation of Invoking Omnipotence as given in Evoking Eternity necessary for a successful evocation? Or is it the Theta/Gamma state that is really necessary and the meditation is just a means to attain it?
In both Works of Darkness and the Become a Living God e-book, the instructions given for evocation do not mention the meditation for Invoking Omnipotence, just meditating down to Theta/Gamma. Neither book gives a power source for the ritual (like the Omnipotence meditation), so I am wondering if Theta/Gamma is all that is really needed.
Any thoughts?

It’s best to have yourself built up with energy. Without a focus on this you still naturally provide a power source but the more the better in this case. In WoD the Black Magickan is to breath in and commune with The Darkness. This practice at first may be draining but becomes energizing. It’s omnipotent Darkness… it’s conscious energy that is all around.

Thanks for your comment, UndeadGod333.
Elsewhere on this forum it has been said that the Darkness meditation is more of a communion, rather than a method of powering the ritual. I, and others, have wondered if the Darkness meditation could be used in place of the Invocation of Omnipotence, and the more knowledgeable among us have said no, it is simply to align yourself with the Powers of Darkness. The ritual of evocation given in BALG does not have any sort of channeling of Omnipotence involved, it just mentions the Theta/Gamma state. Its a tad confusing.

It really depends on you, at the core you don’t actually need anything. But you have to be fairly advanced(maybe?) and have a deep understanding on why, something that doesn’t translate into words very well. The ability to just click into that mindset is where it’s at.
But when you start out you usually need something to get you there, whether that is E.A.'s invocation of omnipotence, kabbalic middle pillar, shamanic dance or the many other varied rituals and spells.
The theta gamma sync is the brainwave pattern observed when one is in a mystical state, it is E.A.'s scientific way of describing that powered up state that these rituals get you in.

As I mentioned, It’s omnipotent Darkness. The advanced Black Magickan will draw in acausal energy/Darkness, fill himself up completely in order to evoke The Dark Gods… sure sounds like invoking omnipotence to me ; )