Instructions
Leave the Wu Shu Academy. The portal will bring you to the outskirts of the Living Forest. Enter the forest, which is full of traps and snakes. Avoid as many of these as you can.
Defeat the henchmen of the Brotherhood of Shadow to proceed to the next area. Heavy and light attack combos will destroy the henchmen. You will see a tiny waterfall to the right.
Jump over the gap in front of the tiny waterfall and approach the door to the right of the screen.
Go through the door. You'll see a tall stone column just to the right of this door. Go past the column and Clay Statues will come to life and attack you. They will be holding shields to defend themselves. Destroy these shields to make your attacks more effective.
Destroy all but one of the Clay Statues. Make sure that you don't destroy the last Clay Statue, or you will have to start over.
Lure the last Clay Statue to the stone column that's closest to the door you entered earlier.
Grab the Clay Statue and throw him into the stone column, which should come crashing down.
Exit the door to return to the tiny waterfall. The waterfall will be gone, revealing a "koin" with a picture of Reptile. Pick up the "koin" to unlock Reptile as a playable character.