Defeating The Dragon
After you exit the Computer Room, you will face a Dragon. To defeat him, shoot him in the mouth approximately twenty times. You will know that you are hitting him, because he will flash yellow.
Note: After the dragon is destroyed, re-enter the computer room, and re-input the suicide command. This will allow you extra seconds to escape. In addition, it may be usefull to make a map of the exact way out, so you won't waste time getting lost!
Invincibility
In room C-3, you can become invincible. Before you go into room C-3, collect the Zillion Power from room A-6. This will allow you to open the containers that are present. After you have the Zillion Power, enter the room and you will see an elevator next to an energy barrier. Get in the elevator, reach out and touch the energy barrier, while pressing down on the Directional Pad. Repeat this, until your energy drops to zero. If this is done correctly, the bottom of the elevator will fall out, and you will be invincible.
NOTE: Once invincible, the pause button will do no good, which means you will not be able to change characters.
Continue game play...