Red Switch Palace

The Red Switch Palace is the third Switch Palace that Mario or Luigi can encounter in Super Mario World and its reissue. It is found in the Vanilla Dome and unlocked by finding the secret exit of Vanilla Dome 2; coding inside Super Mario World indicated that the Red Switch Palace would actually have been encountered much later (in fact, nearing the end of the game at the Valley of Bowser). This level cannot be replayed after it has been completed.

Overview
The palace consists of two rooms, which the player has 200 seconds on the timer to complete. The first room has eight Koopa Troopas, each separated by a Brown Block, with one Koopa next to a Yellow Shell. There is a Switch Block and a line of coins above the Koopas. The first Koopa enters the Yellow Shell and becomes a flashing shell. The player can press the Switch Block to turn the coins into blocks and vice versa, then jump onto the blocks above and run to the end of the room before the Switch Block's effect wears off. The flashing shell follows the player below and defeats the other eight Koopas, earning the player an extra life.

The second room is empty except for the red ! Switch, which is activated by jumping on it.

Enemies

 * Koopa without a Shell: 1 (yellow)
 * Koopa Troopa: 8 (3 green, 3 red, 2 blue)
 * Flashing shell

Gameplay effects
When the red ! Switch is hit, all red Dotted-Line Blocks become Red Blocks. These blocks help the player progress through levels by filling in certain gaps and allowing easy access to a few secret exits.

Levels with Red Blocks
Red Blocks can be found in fifteen levels:
 * Vanilla Dome 1
 * Vanilla Dome 3
 * Cookie Mountain
 * Butter Bridge 1
 * Forest Fortress
 * Chocolate Fortress
 * Chocolate Island 1
 * Chocolate Island 2
 * Chocolate Island 4
 * #6 Wendy's Castle
 * Valley of Bowser 1
 * Valley of Bowser 2
 * Front Door
 * Star World 4
 * Star World 5