How about epistemicologically useless? What caused your hyper-powerful creative entity? You haven't accomplished anything, you've just added another black box to your collection.

This is essentially what username2 was getting at, but I'll try a different direction. It's entirely possible that "what caused the big bang" is a nonsensical question. 'Causes' and 'Effects' only exist insofar as there are things which exist to cause causes and effect effects. The "cause and effect" apparatus could be entirely contained within the universe, in the same way that it's not really sensible to talk about "before" the universe. Alternatively, it could be that there's no "before" because the universe has always existed. Or that our universe nucleated from another universe, and that one could follow the causal chain of universes nucleating within universe backwards forever. Or that time is circular. I suspect that the reason I'm not religious is that I'm not at all bothered by the question "Why is there a universe, rather than not a universe?" not having a meaningful answer. Or rather, it feels overwhelmingly anthropocentric to expect that the answer to that question, if there even was one, would be comprehensible to me. Worse, if the answer really was "God did it," I think I would just be disappointed.