Thunder Woods is the first level in the fourth world of A Koopa's Revenge 2, or AKR2 for short. It is the third level to include rain in the game.
- There is a secret exit in this level that leads to World 4-3.
Except for the notice, follow all the steps from below, but stop at the underground section part. Once you reach that step, go to the end of the section and go onto the top of the green pipe. There are 2 hidden blocks; they make a stairway to the top of the wall. Once you're on the second block, jump to the right. You'll be led to a snow area that has both horizontal and vertical scrolling. Complete it and you will have found the exit.
- You can find Roy Koopa in this level.
(NOTE: You will need either the Screw Attack ability, the Mini Mario from the end of the section, or the Thunder Flower.)
To go there, at the beginning of the level, crouch when you are on top of the first orange pipe, then go back to the beginning. An orange pipe will be shown there along with a trail of coins leading to it. Enter the pipe, and then you'll be in an underground section. Using the Screw Attack ability or the Electric Flower, break the bricks to collect the star with Roy's face imprinted onto it.