Locating the Zone entrance[edit]
Only two zones remain, and now that you have the defense suit, it doesn't much matter which order you tackle them in. One zone is closer to Zone 8 than the other, so visit that one first. In order to get there, you'll need to retrace your steps from Room W to Hidden room d, then to Rooms V, U, and back up to F. When you reach F, face South, and take the right doorway to the backyard of the house. If you continue right, you'll find a little shed with another door in it. Enter that door to find Room G.
Room G[edit]
For a room in a little shack, you'll find at least two useful items, like a supply of grenades and a health restoring potion. Along the North wall, you'll find a door and a window. It is the window that serves as the entrance to Zone 9. Be sure to fill your health up as much as possible, and collect as much ammo as you can before entering. When you're ready, head through the window.
Into Zone 9[edit]
There are two major parts to this zone. The first part contains water, and continues to the middle of the zone. You'll have to wade through the water which is inhabited by fish while dodging other enemies like bats which enjoy hanging out over the little partitions of land that interrupt the water. It is best to jump high and out of the water as much as possible, as you can bypass long segments of this section with each jump.
The beginning section of the second half of the zone is another interesting section. Here you will encounter blue heads that rise up over the land in the background and fall down to the ground below. They bounce once, and then when they are a little off the ground, the explode and shatter into four pieces that spread out in two directions. If you do not kill these heads before they explode, you are likely to get hit by the pieces. It's a good idea to time your progress through the area so that you arrive in time to stab the heads and can continue on to the next one.
Boss[edit]
The boss of this zone begins the battle as one long giant skeletal snake. However, when you take shots at it and hit it along its spine, it will begin to break up into separate pieces that fly around the room on their own accord. In order to defeat this boss, you may ultimately have to defeat each and every piece of the snake by breaking it apart into individual sections, and shooting the heads of the snakes until they are defeated.
If you hit the head, that entire section of the snake will die. As such, if you manage to hit the head of the boss before it even splits, you can kill it very quickly without having to worry about many segments of the boss flying around.
Two things will help you tremendously during this fight if you are unable to kill it without splitting it up. One is using the machine gun. As separate pieces, the bullets you fire will all have a high likelihood of hitting one of the pieces that you create. The other will be to hang out on the ledge along the far left of the room where you came in from. Most of the snake pieces will drop down below your feet and return to the left without hitting you, so you can remain relatively safe there.
The boss is protecting a blue potion, which will restore 100 HP to your health. You can collect it at any time. It will also provide you with the ninth laser gun pieces, leaving only one more to collect until it is fully assembled.