Area 4 enemy evolution
- When you begin the area, you will have to immediately fight an enemy to your left. Continue walking to the left, gown the steps, through the gate, down the elevator, and exit to the right. Walk a short distance to the right to reach door A. Inside, you can purchase a worthwhile power-up for the Rolling Shot for 60 units of energy.
- After purchasing the upgrade, return to the starting point, and proceed to the right. Carefully clear out the enemies in your path as you make your way to the gate. Take the elevator up one flight, and exit to the left. Walk until you reach the platforms over the gap, marked by the 1 on the map.
Cross this section carefully!
- This is an extremely dangerous area to cross. The white insect that flies across the screen will be a constant source of trouble as you attempt to jump between platforms. Arm yourself with your upgraded Rolling Shot, and be sure to fire it when the insect comes within range. Also be sure to clear out any enemies on the opposite sides of the platforms before you make any leaps across. If you fail to successfully land the jump, you will fall in the gap and die immediately.
Once you safely make it across the platforms, head through the gate, ride the elevator up, and exit to the right. You will reach a door (not marked on the map) where a man inside will inform you that you can't proceed without "changing your form." Crawl through the tunnel and continue along. You will see a passage on the left pillar that is too high to reach. If you follow the floor, you will only reach a dead-end. In order to proceed, you must jump up to the ledge of the high platform, and jump up again to strike the top of the right pillar to reveal the hidden entrance to passage a.
Expose this hidden entrance
- Jump through the passage, and cross the hallway to door B. Inside, a lady will tell you that you look great, and that she would like to put make -up on you. The result in the original game makes you look like a hulking monster, while the North American prototype makes you look more like a cyborg. Either way, for as long as you remain in this form, you will have the power to smash your way through certain blocks (although you lose the ability to crawl).
Return through passage a in your new form, and begin bashing the blocks that prevent you from traversing the high platform. Break every block that you see, as many contain energy coins, health syringes, and even 1-up dolls! Jump up to passage b, and walk all the way to the left of the area that you arrive in. When you reach door C, enter it and the inhabitant inside will give you the Psycho Blossom weapon free of charge.
Break every block that you find.
- Return through passage b to the original area, and continue moving to the right, breaking blocks as you go. Make your way to passage c, and pass through it. Walk a short distance to the right and you will reach another door (not marked on the map). At this point, you must head inside and ask the lade to remove the make-up so that you can resume crawling and continue through the tunnel to the right.
- Once the make-up is removed, proceed to the right and crawl through the tunnel. Keep going all the way to the next gate, removing enemies that you encounter along the way. On the other side of the gate, continue right and you will see a high passage which is the exit point from the boss den passage. A little farther, and you will reach passage d.
- Passage d leads to a hallway containing many more passages. Visit each one as you encounter them.
- Passage e leads to an outside area very similar to those found in the previous area. Behind door D is a shop that sells the Psycho Barrier.
- Passage f leads to a much longer outdoor area where you must walk along the floor to reach door E to the left. Behind this door, you will find an inn where you can rest and restore your health.
- Passage g leads to yet another hallway with more passages.
- Passage h leads to a short section where you walk to the right to reach door F. In there, you can buy the ultimate weapon of the game, the Thunder Sword, for 160 units of energy.
- Finally, passage i leads to the entrance of the boss den. Drop down to the floor, walk to the gate on the left, take the elevator down, and exit to the right to face the boss.
The ultimate evolutionary form of the purple aliens from this area is a large purple humanoid who bounces from one side of the room to the other. It leaps straight up into the air, and then dives down diagonally to the opposite corner of the room. All the while it shoots projectiles diagonally at Dan. This is another fight where Dan is safest by remaining in the center of the room. Despite the powerful look of this boss, it is surprisingly susceptible to most of your weapons, particularly the Psycho Blossom and the Spider Shot. Even the Rolling Shot can be an effective weapon in this fight. Even if you lose this fight and are forced to take the passage from the den, you won't have very far to go to recover lost ground and return to the boss.