I was familiar with the scene, but I didn't expect the stage to start transforming like that. For several seconds, I wasn't sure what I was looking at. I didn't think it was actually slanting upwards like it was, because that would put Brunhilde in danger of sliding down the thing. Lol... Obviously, she was anchored to the stage somehow.
For a nice summation of the whole operatic cycle, here's a documentary:
And the whole thing in 2.5 minutes: