Star World 1

Star World 1 is the first Star World level accessible by the Donut Plains Star Road in Super Mario World. The main characteristics of the level are the amount of Rotating Blocks and a rare red-colored Baby Yoshi. The Ground Theme plays in this level, despite the level taking place underground; a trait unique to this level. It is also the only Star World level in the original game to feature Dragon Coins.

Overview
The level consists of one really tall underground area, and a short screen with the level goal. The player starts at the top of the underground area, next to a Super Mushroom, and has 300 seconds on the Timer to finish. The level features many rare items, including three Super Stars and a 1-Up Mushroom. Wielding a Cape Feather allows the player to be able to spin the Rotating Blocks instead of just Spin Jumping to destroy them. As with all Star World levels, there are two ways to complete the level.

Normal exit
The normal way to beat this level is to Spin Jump through the Rotating Blocks all the way to the bottom. In order to collect all the Dragon Coins along the way, the player should Spin Jump each group of turning blocks in this order: If the player collects all the Dragon Coins, an extra life will be awarded.
 * 1) Middle right (seven blocks from the right)
 * 2) Left (six blocks from the left)
 * 3) Left (six blocks from the left, if the player has a Cape Feather, spinning to the right after collecting the Dragon Coin yields a 1-Up Mushroom)
 * 4) Anywhere (the fourth group of turning blocks contains no Dragon Coins)
 * 5) Middle left (eight blocks from the left, grab the Dragon Coin then continue straight down from where the another Dragon Coin appear).

After that, the player should make their way through the remaining turning blocks on the left, grab the star, and run on top of the turning blocks until they can drop down. Then the player should change directions and repeat, picking up the red-colored Baby Yoshi along the way, and feeding it enough Koopa Troopas and Koopa Paratroopas to make it grow. Once at the bottom the player simply needs to go through the Warp Pipe on the right and cross the goal waiting on the other side.

Keyhole exit
To find the Key and Keyhole, the player should Spin Jump down the right-most turning block column until a platform with both the Key and the Keyhole is reached. Beating the level this way will allow the player access to Star World 2, and to the Star Road that warps the player to Vanilla Dome (though the player will not be able to go anywhere if they have not yet cleared #2 Morton's Castle and unlocked the secret exits in Vanilla Dome 1 and Vanilla Secret 1).

Trivia

 * If the player is riding on Blue Yoshi with the key to the secret exit while on the exact horizontal coordinate where the keyhole is and lets the time run out while high enough from the key to reach it, Mario will go to the secret exit while he is showing his defeated pose as soon as he and Yoshi touch the keyhole.