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Yoshi's Island is the first world in Super Mario World. It contains seven levels, including the Yellow Switch Palace and Yoshi's House, which could not really be considered a level.

The difficulty for this zone varies between wide open areas that are easily traversed quickly and Iggy's Castle where you can't take advantage of Yoshi.

Levels

• Yoshi's House
• Yoshi's Island 1
• Yellow Switch Palace
• Yoshi's Island 2
• Yoshi's Island 3
• Yoshi's Island 4
• Iggy's Castle

Enemies

• Red Koopa
• Goomba
• Boo
• Iggy