If you remember in World 7-2 in NSMBDS, there was a platform which rises Mario, and if you stand on either side, you would go into that side. Well, I'll be showing you how to recreate that in Super Mario Maker. The downside, however, is that it won't rise, but you can still make it move sideways.
You'll need a couple of munchers, a monty mole and a bullet bill blaster. You'll need to place them in a upside-down triangle, with the monty mole being at the end, the bullet bill blasters on the top, and the muchers in the middle. This is how it should turn out.
Well, this is how it should look like. Unfortunately, though, since Super Mario Maker can't put 2 enemies next to eachother and still be stacked, you'd have to spread them out. 6 blocks should do
Credits to Ceave Gaming who found this out, and who wrote a tutorial.