How to clear Forest of Illusion 1 in Super Mario World for the Super Nintendo Entertainment System and Game Boy Advance.

How to Clear Forest of Illusion 1
Go to the right and there will be a Wiggler. If you try to stomp on it, it will just turn red and move around more quickly. You can defeat it by having Yoshi eat its head or by throwing something at its head.
To the right, there is a Prize Block that contains a Fire Flower, followed by a red Koopa Troopa. If you have Yoshi, you can jump on top of the Prize Block, then jump left to get the Pink Berry. Then there are some gaps, and red Koopa Troopas between the gaps that are partly hidden by the trees.
After that, there is a Prize Block that contains a Yoshi's Egg, followed by a Wiggler, two Goombas, and a Para-Goomba. Then there is a Wiggler, and a Jumping Board that you can use to reach the Pink Berry in the tree for Yoshi to eat. If this is the second Pink Berry that Yoshi has eaten in this level, he will lay an egg that turns into a Yoshi's Cloud. If you follow the cloud and collect all ten Bonus Coins that it drops, it will then drop a 1-Up Mushroom and fly away. You will have to backtrack to return to the area where you found the Jumping Board.
To the right of the Jumping Board, there is a Wiggler under some Jump Blocks. If you hit the regular Block, a 1-Up Mushroom comes out. To get it, you have to hit a Jump Block when the 1-Up Mushroom is on top of the right side of the Jump Block. This will make the 1-Up Mushroom bounce up and land on the Brown Blocks, and you can get the 1-Up Mushroom after it falls from there.
To the right, there are several Wigglers that are partly hidden behind the trees.
Next, you reach the Midway Gate, which is followed by a Roulette Block and a red Koopa Troopa.
After this, there is an area with Blocks above the platform that have monsters hidden in them. When you get close, the monsters will pop out and fall to the ground. There are also two Wigglers in this area.
Next, there is an area with some floating logs, and more Wigglers and more monsters hiding in Blocks. Below these logs, you will see a keyhole. If you want to use the keyhole, go to the right, and there is a Prize Block beneath the right side of the floating logs. Hit it to get a Power Balloon, then float to the left and get past the red Koopa Paratroopa. Hit the Prize Block near the keyhole to get the key, then wait to deflate if you're still Balloon Mario, then use the key in the keyhole. The level will end and the path to the west will unlock, and you can go to the Forest Ghost House.
Otherwise, go to the right from the floating logs, and there is an area with two Wigglers, followed by a pipe, and an Amazing Flyin' Hammer Bro. Hit the Bro's platform to defeat it, but beware of the Wiggler in the area beneath the platform. Use the platform to reach the right side, where you can go to the right and go through the Giant Gate.
After the Level
If you went through the secret exit, the path to the west will unlock, and you can go to the Forest Ghost House. If you went through the Giant Gate, the path to the east will unlock, and you can go to Forest of Illusion 2.