Night Stalker (0)

Overview
Night Stalker traps players in the middle of a cavernous , with no hopes of escape. The objective is to last as long as possible while blasting as many enemies as possible using guns strewn throughout the maze. A steady "heartbeat" sound serves as the game's unique soundtrack amidst the sound of bullets.
Night Stalker was released for the in 1982. It was ported to the (under the name Dark Cavern),, , and shortly afterwards.
History
Night Stalker was the first and only game created by Steve Montero as a lead programmer, and began development in 1981. While its frantic gameplay became an instant hit amongst other programmers at the office, the game's difficulty changed somewhat when a 12-year-old was allowed to playtest the game and outperformed everyone at . The spider's unique ability of laying down player-slowing web was scrapped to make room for a more difficult enemy: the .
Gameplay
Once a gun has been picked up, the player can begin to fire at enemies. Each gun contains six bullets, and only one bullet from the player may be on the screen at any time. When all the bullets have been used, a new gun appears somewhere in the maze, and the process begins anew.
The player can only die if shot by a robot. If this happens, the lives remaining will appear briefly in the lower left corner, the player respawns in the bunker, and a new gun is placed in the maze.
Enemies
At any given time, a maximum of four enemies will patrol the : a spider, two support enemies, and the main . Only robots can kill the player.
Spider
Bat
Bats can be killed by a single bullet or robot fire, and when the score is under 5000, new bats will respawn to replace their fallen comrades. Once the score surpasses 5000, any killed bats remain dead permanently, and grey robots spawn to replace them.
Grey Robot
Blue Robot
White Robot
Black Robot
At 50,000 points, the black robot's bullets are upgraded, and turn into yellow energy shots capable of destroying not only bullets, but the center bunker as well. If the black robot is allowed to shoot the bunker, there will be no constantly safe area for the player to hide for the remainder of the game.
Invisible Robot
In the event the player reaches 80,000 points, the toughest robot comes out to play -- the invisible robot. The only way to determine this robot's exact location is through the bullets it fires; otherwise, it is virtually impossible to track.
The invisible robot is actually just a black robot colored blue to match the maze's background. Its shape is visible when it is hit the first and second time, and through some of the energy blasts it fires. Its behavior appears to match the black robot's, as well, and its energy blasts will also absorb bullets and destroy the bunker (if any pieces are remaining at this point).
Strategy
It is first important to remember that the cannot process input from the disc and numpad on one controller at the same time, making running and shooting at the same time difficult. However, if one controller is used to move, and the other to shoot, running and gunning is much easier. This two-controller technique is extremely handy for precision control in Night Stalker, where dodging robot fire is a necessity.
Once the score surpasses 5,000 points, it is advisable to avoid shooting bats, to prevent additional robots from entering the maze. While the bat deaths are inevitable, leaving them alive makes the main robot more vulnerable and easy to target.
Another important but often overlooked nuance: While the player can only have one bullet on the screen at a time, the robots also can only have one bullet on the screen at once, even if three robots are in play. This can be used for evading robots, as if a stray bullet is traveling down a long side corridor, the robots cannot harm the player as he runs about the maze. This technique can also be used to exploit and effectively "" the robot entrance at the bottom. The grey and blue robots can be repeatedly killed by well-timed bullet as they slowly enter the maze. Later robots can be tricked into firing their bullet by the player peeking out around a nearby corner, and once the bullet passes by, the player can drop down and fire off quick shots to destroy the robot with ease.
This act of dodging robot fire and returning fire becomes especially handy as the game progresses, most notably with the black robot's bullet-absorbing blasts.
Scoring
Points are scored, unsurprisingly, by shooting enemies.
- Spiders: 100 points
- Bats: 300 points
- Grey Robot: 300 points
- Blue Robot: 500 points
- White Robot: 1,000 points
- Black Robot: 2,000 points
- Invisible Robot: 4,000 points
Extra lives are earned every 10,000 points.