Found them with the help of FB friends. Go to the pyramid with the lasers. Just below the centre of the pyramid, you will see a small room with two broken pipes, and several fires burning. On either side of the fires are two secret rooms that you enter by breaking a slightly darker grey wall tile. When you clear those rooms, a lion appears. If you are like me, you have probably missed one of these rooms. The one I missed had exactly 14 tiles in it. I also missed a breakable wall tile somewhere else. Good luck. I tried to attach a screenshot, but the upload was unsuccessful.