Night Stalker is a top-down maze shooter released in 1982 for the Mattel Intellivision. You are trapped in a maze while robots, spiders, and bats relentlessly track you down. The key to survival is to destroy as many of them as possible -- before they get you!
While the robots only spawn in the lower left corner of the map, the player is normally given an incentive to wander throughout the maze when ammo spawns in a far away location. TheWinslinator and SuperMonkeypotato make the game look too easy by manipulating ammo to also only spawn in the lower left corner for the fastest robot massacre in history! The robots aren't shown any mercy once an Invisible Robot is killed, which appears after 80,000 points is reached, and marks all of the game's content being showcased.
Objectives
- Uses hardest difficulty
- Uses two controllers
- Heavy luck manipulation
- Genre: Action/Shooter
General Information
- Game speed does not increase as you play Night Stalker, unlike most Intellivision games.
- Spider, bat, and gray robot movement is random. All other enemies seek the player.
- RNG can be manipulated by the timing and direction of the player's shots.
- Normally, you cannot run and shoot at the same time, but using two controllers (one for running, one for shooting) resolves this issue.
- Only two bullets can be in the maze at once: one from the player and one from enemy robots.
- Bullets can be shot at four different vertical positions in the corridor where the robots spawn.
- Collision detection in this game is extremely accurate, so you need to take all subtleties in enemy/cave geometry into account to save frames. For example, aiming at height 1 (see figure) kills this robot the fastest, but aiming at height 2 despawns the bullet quicker. Each are due to the robot/cave geometry jutting out slightly farther than the other heights.
Ammunition You get bullets by collecting guns which can spawn in five locations throughout the maze (see diagram below). Each gun gives you six bullets, and the location of the next gun spawn is determined by the frame your sixth bullet shot despawns. With the exception of the first gun, we manipulate the gun to always appear in the lower left corner so we can immediately wreck any robot which spawns. This gun spawn manipulation is the most significant source of timesave over any RTA run.
Points Table Spider = 100 | Bat = 300 | Gray Robot = 300 | Blue Robot = 500 | White Robot = 1000 | Black Robot = 2000 | Invisible Robot = 4000
The Spider He sticks around the entire game and is only worth 100 points so we ignore him most of the time, unless we have to wait a while for the next robot to spawn.
0 - 4900 points 1 gray, 2 bats. We have two options for this segment: go right and kill some bats, or go left and focus on the gray robot and spider. While initially it may seem faster to grind for points on the bats, their longer respawn time and the HUGE walking distance you will need to make to the lower left corner when 5000 points is reached makes that option unoptimal. So, we instead focus on the gray robot and spider. However, at 5000 points, gray robots will spawn in place of the bats. For this reason, we need to kill the bats as we cross this threshold. Both bats were manipulated to a location where they could be easily shot by the player and gray robot.
5000 - 14900 points 1 blue, 2 gray. Now that a bunch of robots are spawning in the lower left corner, our rate of point increase skyrockets; but we run into a new issue: a glitch which we will refer to as "phantom shots". When destroying these new gray robots on the first frame they spawn, bullets will randomly shoot at you from thin air! We believe this is due to the game calculating the destroyed robot's projected path, and shooting bullets from those positions. The phantom robot appears to "die" when its gray counterpart spawns again.
15000 - 29900 points 1 white, 2 gray. The white robot takes three hits to kill as opposed to one. Not much changes in terms of strategy.
30000 - 79900 points 1 black, 2 gray. By this time, both gray robots have been manipulated to spawn simultaneously for much easier shooting. The black robot shoots gigantic "energy bolts" which neutralize the player's bullets if they touch. Luckily, there is a single pixel above the bolt which we can slip bullets by, so this isn't much of an issue. At 50000 points, the energy bolts change color from white to yellow. These new bolts are capable of destroying the bunker in the center of the map.
You can sometimes be awarded 2300 points for destroying a black robot (and rarely, 1300 for a white one). As of this moment, we have no idea why this happens. However, we do know that having other sprites (energy bolts, other robots) nearby, and walking upwards as the robot is destroyed can increase the chance of getting the bonus. Through trial and error, we get as many of these kills when optimal.
80000+ points 1 invisible, 2 gray. The invisible robot is the last robot type. Well... he isn't technically invisible, just assigned the exact same blue color as the background. Otherwise, he's identical to the black robot. His death marks all of the game's content being showcased.
I'd like to thank SuperMonkeypotato (SMP) for some of the techniques used in this TAS, special assistance, and allowing this project to finish in a timely manner. He will also be helping me in our next TAS, AD&D: Treasure of Tarmin, so I look forward to working with him again. I'd also like to give shoutouts to baldnate and Intellivision Master for their competition towards bringing down the RTA 80,000 Points time!
Suggested publication notes Just go ahead and copy/paste the first two paragraphs.
Suggested Screenshot Frame 2949
Memory: Updating with file that defeats the invisible robot.
Memory: Aside from potentially looking further into what causes some robots to give more points at times, this appears to be as optimized as it gets.
With the movie now defeating the invisible robot, it can be considered to complete all new content.
The rules have been updated to clarify that the new content is to be completed, not just spawned in.
The movie received much mixed response. While some responses were positive, the rest of it was fairly negative. The movie is very repetitive, without much variation therein.
Accepting to Vault.