You begin the game at the left end of a long hallway. Doors line the hallway, and there are stretches where a second story is visible above the ground. You will first encounter the most basic type of enemy, the purple hoods which have no special attack, and are defeated with one bullet. Shortly after you fight a few of these, you will encounter the enemies in yellow hoods. While they have no special attack, they require two bullets to defeat. Getting hit by one bullet will only knock them to their knees before they recover and stand back up. Get to know the behavior of these enemies.
It’s not necessary to kill every enemy, just every threat. Only experience will teach you whether an enemy is a potential threat, or if they are just milling about. Enemies standing on platforms above you may decide to drop down. Enemies standing below you may jump up to your level. Count on at least one enemy exiting through each door that you reach. For this reason, it’s a good idea to stop just before every door and allow an enemy to walk through so that you can quickly shoot it and eliminate the danger of getting ambushed as you pass the door.
As you make your way to the right, you will see a sign indicating that there’s an ammunition cache behind a door. Press up in front of the door to enter and obtain fifty more bullets. You will eventually come out automatically, but you can hold the joystick up if you are concerned that an enemy is about to walk in front of the door, and you want to wait for him to pass. A little further down the hall will be another sign indicating the presence of another weapon, the machine gun, and 100 rounds. Collecting this weapon will make it easier for you to mow down large groups of enemies.
Ordinarily, you can only enter these doors and collect their contents once. However, if you wish to take extra advantage of this weapon, you can walk forward to the start of the next second level platform, and then return to the door. If you advanced far enough, you will trick the game into thinking that this is the first time you’ve been through this door, and it will award you another 100 rounds of ammunition. By moving quickly, you can make use of this trick to obtain over 200 machine gun bullets before you are pressed for time and must advance.
Eventually, you will meet other types of enemies including orange hoods in red suits who carry a gun and will fire it at you, but they are defeated with a single bullet. This compares to the blue hoods in purple suits who also carry a gun, but take two bullets to defeat. There is also the gray hoods who lob grenades at you. They are defeated with one bullet. You are likely to encounter larger groups of enemies at you continue down the hallway, so make efficient use of the machine gun bullets to clear the path ahead of you. When you reach the end of the hallway, you will encounter a flight of stairs. One lone gray enemy awaits you on the opposite side of the stairs. Then hop down to the bottom to proceed through the second half of the stage.
Continue to stop before every door and allow an enemy to exit before pressing on. Eventually, you will reach a set of tires piled up on their side. Though not visible from the player’s angle, they are in fact hollow in the middle, allowing Albatross and enemies to stand or squat inside the gap. Enemies will use this to their advantage by squatting down and standing up to fire a weapon at you intermittently. Carefully time your shots at them so they get hit when they stand up, and squat down when they fire a bullet at you.
After clearing the first set of tires, you will have to cross a mix of tires and sandbags. Ultimately the tires will cease, and you will only encounter sandbags on the floor. Keep your eyes on any enemies who will be approaching you on foot, especially if they are on a different level from you. If they are below you, wait until they leap in the air before shooting. If they are above you, travel back to a section where the ground is more level, and you can safely put some space between you and any threat.
Once you make it to the end of the sandbags, you will see a door to the right. This is the stage exit. Clear away any enemies that stand between you and the door, and approach it when it’s safe.