Valley of Bowser 3

Run or jump over the incoming Koopas to reach a block on a higher ledge to the right, which contains a powerup.

Jump onto the first falling platform (marked with a '1') and note that it falls after 1 second; this mechanic applies to similar platforms throughout the level.

Cross two of these falling platforms and jump onto the lower white column.

Proceed across another platform, collecting a Dragon Coin on the way.

Continue across more falling platforms until you encounter two Koopas flying vertically. Bounce off the left Koopa, then the right Koopa, and finally onto the lower platform.

Collect the Dragon Coin and jump onto the platform above, then onto the white column before you slide off.

Jump onto the first platform in the next section and collect the Dragon Coin as you drop, landing on the 4-second falling platform below.

Reach the yellow pipe and play the 1-Up minigame. Exit at the top to return to the level.

Use the springboard to the right to reach the midway checkpoint (an auto-save point you restart from on death) above. Move the springboard to the right to hit a '?' block.

Use the springboard to the right to land on one of the three platforms and cross the valley, avoiding jumping Koopas.

At the other side, descend onto the platform and then onto the 4-second falling platform.

Continue on this platform to a point where you can choose a higher or lower platform; take the lower one to get a Dragon Coin.

Bounce off a giant Bullet Bill that approaches to reach the higher platforms to the left (e.g., the 4-second one).

Continue taking platforms to the right, jumping over giant Bullet Bills as needed, until you reach the level's exit.