Since this route only unlocks one power up secret house, it may end up being faster to unlock one later on in the route since the cape is so important and continually going back to world 2 is super slow. Crystal Cavern's secret might be best. After flying up for the shortcut, hit the box on the right and bring key through the pipe you just came out of.

-Misty Isle (all normal exits) -Salty Isle -Desert World 1 -Desert World 2 (secret with spring clip) -Desert Pyramid (normal: bring cape to fly to the top right at fourway path, go to pipe above for p-switch, bring it back and go to bottom left at the fourway, use a power up to damage boost through the bottom left path below the line guided platform and mace balls) -#2 Desert Castle (normal: top path) -Water World 1 (normal) -Water World 2 -Water World 3 -Ship Graveyard -#3 Water castle (normal) -Crystal Cavern 1 (normal: bring cape, fly up at the wall) -Vacant Ghost House (secret: bring cape, just fly up) -Crystal Cavern 4 (bring cape to fly at the end) -Crystal Cavern 5 (only hit one invisible block bridge in the open water section to drop down with the blue switch) -#4 Crystal Castle (normal: run under the small only layer 2 section with a power up and cape in box with the screen scrolled right and fly over the lava to skip a cycle. keep the cape to fly over another lava section or get the midpoint and die for safety. second half with cape: hit switch and fly over or under the layer 2 mega spike with cape and get in the door) -Sky World 1 (just fly into clouds lol) -Sky World 2 (normal: just fly under level) -Sky World 3 (secret: fly left, about midscreen) -#5 Sky Castle (normal) -Ice World 1 (secret: go through obvious right wall at vertical climb section) -Ice World 5 (hover into the point where the slope meets flat ground at the top of screen to bypass secret. keep hovering to not fall through upside down slope) -Ice World Igloo (normal) -#6 Ice Castle (normal: bring cape for 2 skips) -Pipe World 1 (normal) -Pipe World 2 (bring power up. pipes: first, right, right, right, up, left, down, down, up, up, bridge, left, down, up up, left, second to last green, down, bottom right, left, right, clip into pipe: close to the middle but to the right while facing left) -Pipe Fortress (bring a cape. p-switch in box forming the ledge, hit it, door to bottom right, fly into roof pipe) -Pipe World 5 (bring cape in box) -#7 Pipe Castle (normal. bring cape. pipes: top, top, fly to right, second from right, second from left, up) -Bowser's World 1 -Bowser's World 2 (normal: scroll the screen right) -Bowser's World 3 (bring a cape to fly over the first interior section) -Reznor's Fortress -#8 Bowser's Castle (doors: first, all the way to right)