I think I'm stuck. Am I missing something? I got the third ring, and expected I could create a third thingy or something, but can't. I've pushed on all the walls and gates. The oracle says I have to go deeper, but falling into the hole just puts me back here.
You aren't stuck, though I could see how the stone would mislead you that way. I may consider putting that somewhere else.
There is another ability you have now with the level 3 ring, not a third block. The hint is when you pick up the ring: "the void cannot consume them" (don't remember the exact wording!)