Defender was a coin operated arcade game released by Williams in 1980, and may reasonably be considered the most brutal, but also the most played arcade game ever created. It's estimated that it grossed as much as PacMan ($1 billion!), the highest of all time.
The story behind the game is that whilst working on what was to become Defender the Eugene Jarvis awoke from a dream with the image of the game lingering in his mind; and then set out to make his vision.
Basically the plot of the game is that you fly a fighter at extreme speed left and right over a wide landscape, most of which is off the screen at any one time. The rest is visible on a radar, at the top of the screen. Sitting on the landscape are up to 10 green and yellow 'humanoids'.
Attacking in waves, green landers teleport in from hyperspace, fall down until they are flying just above the surface, and then, hugging the surface rush off to pick up a particular humanoid. When they reach it they catch it and carry it to the top of the screen, if they make it they change into mutants; which move very fast and fire at a higher rate and are more intelligent and nasty.
However, if the lander is shot before they reach the top of the screen the humanoid falls, and if dropped from too high, will die. The player can however attempt to catch the humanoid with his plane and return it safely to the ground, for which a hefty 500 points is awarded.
Other enemies include bombers that slide around the territory leaving mines in their wake, and pods that explode when hit to reveal swarmers which are small, red, fast and extremely numerous. Finally, there are baiters, which turn up if the game thinks you are taking too long to kill stuff, which happens far too early in the game for anything even remotely close to comfort.
On the players side is a fast repeating laser, a 'smart bomb', a hyperspace button, a button for instantly turning around, a fast rocket for sliding sideways very fast, and a knob that moves the player up and down (relatively slowly).
However, the controls are finger mashingly laid out- and the hyperspace button is almost out of reach; and in any case randomly kills the player. Long term playing of the game leads to an appearance not dissimilar to arthritis (although not as painful or quite as long lasting.)
The game was deliberately tuned to cause the players' hands to sweat- early versions of the game were described as being like in a swimming pool, and about as exciting, but certain aspects of the arcade version such as the baiters definitely set the adrenaline pumping with a vengance. In addition, many aspects of the game randomly kill the player without any hope- the landers fire so quickly that no reaction is possible, baiters can materialise on top of the player or move directly towards the player so that no dodging can be humanly achieved. The aliens are extremely hard to hit, you have to hit certain parts of them to destroy them, and the baiters and swarmers require pixel perfect aiming.
Furthermore, in many cases there are simply so many differently moving objects on the screen at one time that the player is completely overloaded and dies. Even the flickering stars in the background confuse the visual field enough as to hide mines left by bombers- so sometimes the player just seems to die for no obvious reason.
It's all a recipe for a horrible game... and yet no. The game is so hard that there was enormous cache for playing it well, and the graphics, although very tame by modern standards set new standards in spectacle at the time- you practically wanted to die just to see the explosion. Finally, the adrenaline rush of the game was the nearest thing to an addictive experience you can get and still remain legal.
The net upshot of all this is that the game designers, who typically know best how the game works, and thus usually able to play it as well as anyone, were unable to score more than 55,000 points- and it was seriously suggested that that was a fluke. The designers almost didn't add in extra levels because they figured nobody would reach them. However, they hacked something together shortly before release, just in case. That was turned out to be a wise move, because within months the world champion players would be scoring more than a million points...
Upon testing at a show, the players were unable to master the 6 controls necessary to play the game and lasted, on average about 35 seconds, and commentators reasonably expected the game (and incidentally another game at the show called pacman) to bomb, and compared it unfavourably to flying a jet fighter.
The rest is history.
How to Play Well (spoilers!)
There are a number of strategies that can be used to play well, but the game is still extremely difficult:
- when firing, jiggle the plane up and down rapidly to increase the chances of hitting something.
- shoot at the landers as soon as they appear on the screen, or even before, to minimise the chance of being shot(!)
- stay as physically far away from any landers on the screen as possible to avoid being shot(!), and minimise the number on the screen. Shoot at the aliens before they appear on the screen wherever possible.
- understand that the smart bomb has two functions, blow up a random number of aliens on the screen and place a random number of the remaining (often all of the remaining) approximately 180 degrees away on the map from you. The two functions are quite distinct, and the second continues to operate for a few seconds (at random).
- shoot most of your own humanoids early on in the higher levels (but jealously keep 1-3 around to avoid the ground exploding.) This helps minimise the number of mutants, and mutants are about the hardest part of the game to deal with.
- try to carry a humanoid around (fortunately, getting killed whilst carrying a humanoid doesn't kill the humanoid). However land it as soon as the last lander has been killed or mutated for extra points.
- exclusively save the smart bombs for pods or swarmers, and always try to bomb pods in pairs if possible even if that means you have to shoot the odd pod first.
- hyperspace should be used whenever the immediate chances of death are greater than 25%.
- if chased by swarmers, they have a single weakness, once they have passed immediately chase after them from behind- they can't turn around until they get far enough away from you, and they can't shoot you until they turn around, chase them and take them out. They also fire at 45 degrees or less, so pass them at a large angle to increase survival.
- try to keep cool. If you get too stressed your performance of playing the game goes down- remember to breath!
There are a huge number of bugs. Here's some of the more infamous:
- at 900,000 the scoring gets messed up and each lander killed gives another life. However it's more of borrowed, since it means that once you get past a million you don't get anymore lives until the books balance again. Still, it gives a chance for a much needed toilet break.
- the game scans the buttons at a relatively slow rate, when a lot of things are happening on the screen the reverse button seems to be occasionally missed and the plane doesn't turn around reliably
- the ~1 Mhz 6809 processor in the game isn't quite able to keep up with the demands of updating scores of aliens all moving at the same time, the more enemies there are the slower the game runs. To avoid most of the problems the game cheats, and jumps the game forward in big jumps when there is a lot going on, which actually makes it harder (the aliens can become virtually unkillable since they jump right past the eyeline of the player.) There even appears to be code that teleports aliens away from the main screen if it gets too full. The slowdown means that, for example, how long you need to press the up button to line up with an alien varies, and explosions in particular slow the whole game down.
- picking up all the humanoids and firing rapidly essentially freezes the game (all the aliens particularly including the baiters get continually teleported away from you).
After the game had turned into a smash hit Eugene left Williams and set up another company, which then sold stargate aka Defender II back to Williams. This game was not unsuccessful, but never did as well as Defender and seemed somewhat easier.
The Defender game is now playable on MAME, although other legal copies of the game exist. However a true connoisseur will buy an original circuit board from the machine. Modern computers are able to emulate the 6809 machine code, in Java faster than the original 6809 could(!), and there are original versions on the web.