Super Mario Bros. Wonder - Fluff Puff Peaks Special Climb to the Beat

Holy cow! This was the end of about 1.5 hours of attempts and probably close to 100 lives just to complete the stage, not even getting the flower coins. And this is just the first Special World stage, I can't imagine what else there is in store. Probably up there with some of the toughest platforming challenges I've done, just 50 second of pain.