Night Stalker traps players in the middle of a cavernous maze
, 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 Intellivision
in 1982. It was ported to the Atari 2600
(under the name Dark Cavern), Apple II
, and Aquarius
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 Mattel Electronics
. The spider's unique ability of laying down player-slowing web was scrapped to make room for a more difficult enemy: the invisible robot
The player starts with six lives, and always respawns
in the middle of the maze, in the bunker
. Provided the player is completely inside the bunker, robots will be unable to kill the player (until 50,000 points, when the bunker's safety is threatened). A yellow gun will appear and flash somewhere in the maze, and it is up to the player to run out of the bunker and pick up the gun while dodging enemies.
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.
At any given time, a maximum of four enemies will patrol the maze
: a spider, two support enemies, and the main robot
. Only robots can kill the player.
The spider spawns in the web in the upper left corner, and moves randomly about the maze at a slow pace. The spider has a venomous bite, and will knock down and paralyze the player for a few seconds upon contact. The spider is easily killed with a single bullet, but it will respawn in the web shortly after its death. The spider is unaffected by robot fire.
The maze contains two vampire bats at the start of the game, which will awaken from the upper right corner of the maze and fly around randomly. The bats are rather quick, and will bite and paralyze the player for a few seconds upon contact, much like the spider. Their speed makes this paralysis slightly more dangerous, as a bat can move back and forth over a player and keep them paralyzed for an extended period of time, unable to move and susceptible to robot attack.
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.
The first robot the player encounters in the maze, spawning in the narrow passage in the lower left corner. It moves about slowly and randomly, firing at the player whenever it thinks it has a shot, and is easily killed by one bullet. Once the score reaches 5000, the grey robot will replace any slain bats, but no longer serves as the main robot adversary.
The blue robot appears at 5,000 points, replacing the original grey robot. It moves more intelligently than its predecessor, and will move more directly and aggressively towards the player. It is also killed with a single bullet.
The white robot replaces the blue robot at 15,000 points, and will also attempt to aggressively track down the player. The white robot is also much sturdier, and requires three bullets to kill. The first and second bullet hits will cause its shield to flash yellow.
At 30,000 points, the white robot steps aside for the black robot. The black robot moves quickly after the player, and also takes three bullets to kill. This is made even more difficult by the black robot's special white bullets, which will absorb any player bullets that come in contact with it, making crossfire shots worthless.
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.
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).
It is first important to remember that the Intellivision
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 " spawn camp
" 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.
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.