You have two choices, you can start the level with the spark power and Kine, or without. In the 4th room, when you are going up and it is scrolling, when you see the door there is a hidden one to the left. If you have Kine and Spark, just use the ability to light up the room and see the door. If you don't have him, just run to the left and keep pressing up until you get lucky. After that, you'll be taken to a passage leading to Captain Stitch, the giant gordo mini-boss. Beat him, and get the lost frog. Or is it a toad?