Cell Stage II
- Stage 4 is the first of two completely original stages designed exclusively for the NES version. This stage continues with the cell theme introduced in the first stage, only it is oriented vertically. In this stage you will be passing through various organs associated with the circulatory system including the blood stream and lungs. During the introduction, you will face a series of Beruberumu squads which provide power-ups. Eventually, you will see the lining of tissue, and large indestructible purple corpuscles will float down screen. They are followed by red blood cells which drop down the sides of the screen and possess the ability to shoot at you. Your missiles should be effective against them. Occasionally, a wayward corpuscle will fly through that can be destroyed.
- The capillary system will deposit you in a lung region which contains many air sacs. If you allow them to occupy the screen long enough, they will erupt and release three spinning cells which bounce around the area and take quite a lot of damage to destroy. As the screen fills up with these cells, they will absorb the shots that you would otherwise fire at the sacs. You can destroy these sacs before the erupt, removing the threat of the cells they release. Lasers are by far the most effective weapon against them.
- Next you will encounter small nodules of tissue in the middle of the screen. These nodules will be indestructible until they scroll further down onto the screen. When low enough, they unleash a webbing of tissue around them. Once they do this, they become vulnerable to attack. Don't proactively attempt to destroy them. Simply allow them to scroll down until they unleash the webbing, and then move directly beneath them to destroy them. When they stop appearing, you will have a short chance to destroy Beruberumu squads for power ups while some indestructible corpuscles fall from the top.
Naturally, at the top of a spinal column, you would expect to find a skull, and that's exactly what you'll encounter as the boss for stage 4. Giga is a large skull like boss, complete with his own eyeballs, that floats along the top of the screen. When he opens his mouth, he sprays the screen with a series of slow moving projectiles which must be avoided. His weak point is his open mouth. After he sustains enough damage, his eyeballs will begin to freely roam outside of his head, following you all around the screen. It is not necessary to destroy Giga's eyes to defeat him, but it can be helpful. Ultimately, you must shoot him in the open mouth enough times to destroy him.
2nd loop changes: Projectile and eye movement speed is faster.