The third stage will not start off as gently as the first two stages have. As soon as you begin, you will notice how the mountainous terrain dramatically impacts your offensive capabilities. The mounds of stone ahead of you block your shots, while your enemies are typically free to pass right through them to attack. Choosing an advantageous point to attack from is critical. There are two new enemies that you will encounter on this stage. The first are purple skeletons which cannot be killed by any attack other than the mirror images of Dino Riki. If they are hit with a standard weapon, they simply fall to the ground, only to rise up and advance again moments later. If that weren't bad enough, they can still attack you while they are disabled.
The second new enemy in this stage are a set of eight black orbs which surround you and eventually close in on you. If you have the flame weapon, you are very likely to defeat all eight orbs without being harmed. However, if you have any other weapon, you'll need to fire as rapidly as possible in order to eliminate all eight orbs before one can touch you. You'll also encounter dinosaur fossils that spring back to life and advance on you very rapidly. If you get caught in the jaws of these animated bones, you will lose your life instantly. The first of two Riki tiles can be found along the left side of the screen before the first ravine.
If you have wings when you encounter the first ravine, don't be afraid to use them and float over to the right side. There is another wing tile hidden there for you to collect which is easily found. The enemy attacks will increase in intensity as your progress, and eventually, the very ground itself will begin to teat apart and break open before you. If you have the wings, you can hover over the breaks effortlessly, but if you do not, carefully time your jumps between enemy attacks.
After the first series of ground tears, there will be another flat section. Towards the end of this section, the second and final Riki tile is hidden away on the left side of the screen. In order to hit it, you'll have to stand behind the skeleton fossil and fire rapidly. Fortunately, very few enemies will appear while you attempt to reveal it, so it's worth the effort. The wings will really come in handy for the next set of jumps that appear. After that, the boss cavern entrance will appear with one more ground tear, and two power-up opportunities just before you enter.
The boss of stage 3 is a flame spitting giant cobra. Unlike the previous enemies, this one has the ability to teleport around the room. He will materialize in one location, spew a great deal of fire, and begin to disappear from that location before reappearing in another one. You'll have to stay on the move and try your best to predict its next location so that you can get in the maximum amount of firing time before he zips off once again.