Monster Madness

A couple minutes into this level you will come across jail cells on both the left and right sides of the walls. To open then you need to flip the switch to any color. Then go find the corresponding color on the other side of the wall and enter that cell. Do this for every color and head on. Next right you will have another set. Do the same thing and the achievement will unlock. NOTE: there are monsters in each cell that you must kill.