Shoot Em Up

Defender is a Horizontally Scrolling Shooter arcade game created by Williams Electronics in 1980 and released in February 1981.[1] It was designed and programmed by Eugene Jarvis (who later formed Vid Kidz and made more of Williams' hits), Larry DeMar, Sam Dicker, and Paul Dussault. This game was slow to become a hit when it was released as many thought it was too difficult due to its control configuration of five buttons and a joystick. It ultimately gained many fans and remained popular throughout the 1980s. Defender has been described as one of the most difficult significant games of its time.

Development history

At the time Eugene Jarvis first came to the company, Williams was just about to make their move into the fledgling video game market. Eventually, Jarvis was given the job of developing the project. As the project progressed, he eventually got other people involved in the game's development (including Larry DeMar, with whom he would later co-found their company, Vid Kidz). Defender was developed using the "Exorciser", a computer from Motorola that Jarvis describes as "the most bloated, overpriced computer ever created".

Jarvis initially worked on the game on his own, added the scrolling land, and added some humanoids on the land, but lacked a narrative. One night while falling asleep he dreamed of the aliens following the land and picking up the humanoids and carrying them off and then turning into mutants, with the player trying to stop them. He had his game.

Initially the game was too easy, like flying in a tank of water, but the gameplay picked up considerably when 'baiters' were added which appeared after a set time period. The baiters kept the player under constant time pressure to finish the level, significantly increasing the intensity of the game.

At one point, when the game was nearly complete, the highest score anyone had ever managed was 60,000 points, and many people thought that this was a fluke. Indeed, the development team almost didn't add extra levels, as they believed that no one would be able to reach them.

When the time came for the game to make its debut at the AMOA trade show, the game still wasn't complete. The game had everything: its complex controls, its cabinet graphics, and the Defender marquee. However, it was missing one important thing: the ROM chip that actually contained the game.

When the game was finally finished, the machine wouldn't come on the first time the ROM chips were inserted, they accidentally plugged them in upside-down and destroyed the chips in the process, however when the ROMs were "burned" (the method of transferring the game from the development computer to the arcade machine's ROM chips) a second time, it did come on. Unfortunately, nobody would play the game; because of its complex controls, many of the showgoers felt that the game was too complicated to play. In the end it was believed that this game, along with Pac-Man, would fail, and that Rally-X would be the top money earner. The game went on to sell more than 60,000 units—more than disproving these projections—and cemented its place in video game history.


The level of difficulty of Defender is very high.

The player flies a small spaceship above a long, mountainous landscape (in all versions, except the Atari 2600 edition due to memory limitations; in that case, the landscape consisted of a city represented by buildings). The land is inhabited by a small number of humanoids. The landscape wraps around, so flying constantly in one direction will eventually bring the player back to their starting point. The player's ship can fly through the landscape without being harmed by it.

A number of flying aliens reside in the air above the landscape. The player's responsibilities are twofold:

  1. Destroy all aliens
  2. Protect the humanoids from being captured

The player is armed with a beam-like weapon which can be fired rapidly in a long horizontal line ahead of the spaceship, and also has a limited supply of smart bombs (three, to begin with), which can destroy every enemy on the screen.

At the top of the screen is a radar-like scanner, which displays the positions of all aliens and humanoids on the landscape.


Some of the aliens in Defender fire projectiles at the player- these travel at random speeds; the highest speeds are quite capable of killing the player from right across the width of the screen without any chance of dodging; survival thus depends to some extent on accruing enough points to get extra lives.

There are six types of aliens in total:

  • Lander - The primary enemy on every level. Landers teleport into the level in staggered waves. They attempt to capture humanoids by descending upon them and dragging them into the air; if they make it to the top of the screen with a humanoid, the two fuse together into a more dangerous Mutant. Landers fire projectiles at the player.
  • Mutant - A mutated Lander with a humanoid fused inside it. Mutants home in on the player at constant speed, firing projectiles. They move erratically as well as deliberately avoiding lining up with the player's gun making them difficult to shoot. The Mutants have an 'international dateline' near the tallest part of the terrain; they chase the player in such a way as to avoid crossing it.
  • Baiter - flat, iridescent aliens that progressively teleport in if the player is taking 'too long' to complete a level. Homes in on the player and attempts to match his or her speed, whilst firing accurate projectiles. A difficult opponent due to its unbeatable speed and tiny vertical cross-section, which makes it very hard to shoot.
  • Bomber - A box-shaped alien that lays stationary mines in the air.
  • Pod - slowly moving star-like aliens that burst into a pack of Swarmers when shot.
  • Swarmer - tiny teardrop-shaped aliens that move very quickly in an undulating fashion. Difficult to shoot due to its small vertical cross-section. Fires projectiles. Swarmers also have an 'international dateline' near where the player starts each level.

Once all aliens (except Baiters) are destroyed, the player progresses to the next level.


The game starts with ten humanoids inhabiting the land. Landers will attempt to capture and fuse with these during play.

To rescue a humanoid from capture, the player must listen for the cry made by the captured humanoid, look at the radar to see where the captured humanoid is, then shoot the Lander holding it while it is in the air, causing the humanoid to drop back to the ground. At low height humanoids can survive the drop on their own, but if the Lander is killed at too high an altitude, the player must catch the humanoid with their own ship and return them to the ground, otherwise the humanoid will not survive the drop.

The humanoids can be killed by the player's weapon just as easily as the aliens can, so careful aim is required when firing near them.

If all humanoids are killed, the entire planet explodes, leaving the player in empty space. This also has the unfortunate effect of turning every Lander into a Mutant, making the player's job very difficult.

All ten humanoids are replenished every fifth wave, starting with wave five. If the planet explodes, the player has to survive mutant-filled waves until the next multiple of five wave arrives, when the planet will be restored.


As well as the points gained by killing aliens, scores are also awarded for the following:

  • Humanoid falling back to the ground without dying: 250 points
  • Catching a falling humanoid: 500 points
  • Returning a humanoid to the ground: 500 points
  • Humanoid surviving the level: 100 points per humanoid, increasing by 100 each wave until wave 5, then 500 per humanoid every following wave.

The player receives an extra life and an extra smart bomb every 10000 points on the game's default settings, although this can be changed by the operator.

"Tournament mode" is a common competition setting where the player starts with five ships and smart bombs, but no additional ships or smart bombs are awarded. Scores over 200,000 at this setting are extremely difficult to achieve.


The control system of the Defender arcade game is quite unusual compared to that of most shooters. Instead of the standard 'Up, Down, Left, Right' system, it has a joystick to move up and down, a 'Reverse' button to toggle the player's horizontal direction, and a 'Thrust' button to move in that direction. There is also a Fire button for shooting, a button to activate a smart bomb, and a hyperspace button which teleports the player to a random position in the level, at a risk of either exploding upon rematerialization, or materializing onto an enemy or enemy projectile.

In practice, the layout of the controls was uncomfortable for some players. The thrust, fire and smart bomb buttons layout tended to cause cramping of the right hand, and the left hand was uncomfortable also. The hyperspace button was placed in the middle between the two hands, and was very difficult to reach quickly.


The game had some notable bugs and features:

  • The software running on a Motorola 6809 processor struggled to meet the requirements of running the game. When a lot of objects are on the screen simultaneously the game starts to run much more slowly; to minimise this effect, the game randomly teleports aliens away from the player. The game also compensates by moving aliens and the player further to minimise the obviousness of the slowdown, though this caused numerous other bugs and issues, like making the aliens much harder to hit.
  • Related to the previous bug, if the player manages to pick up all the humanoids and repeatedly fires, redrawing the humanoids and firing consumes enough processor power that all of the enemies get teleported away, then the game basically stops.
  • When carrying a humanoid, moving down while firing while the game is running very slowly sometimes causes the player to shoot the carried humanoid.
  • The control keys weren't polled often enough by the software - in particular briefly pushing the reverse button would sometimes be completely ignored (particularly when a lot was happening at the time); in addition the fire button works only intermittently.
  • Once the score reaches 990,000 points, anything the player does that creates points (Shooting a lander=150 points, getting hit by a bullet=25 points, etc) awards the player an extra life and smart bomb until the score rolls over to zero at 1,000,000 points. The player continues with all of the extra lives and smart bombs they were awarded, but they will not get any more until they have reached the score they would have needed to earn them at the game's award level settings. In other words, if the player wins 46 lives with this bug between 990,000 and 1,000,000 points on a machine set to award new lives and smart bombs every 10,000 points, he will not get an extra life until 460,000 points past the rollover to 0 points. However, if the player earns 100 or more ships during this period, the 100 will be subtracted from the computation for the next extra life. For example, if 117 extra lives are awarded between 990,000 and 1,000,000 points, the next extra life will be awarded at 170,000 points past the rollover to 0 points.
  • Related to this bug, the top score any player can ever achieve on the high score board is 999,975 points. If the player rolls the score over past 1,000,000 points to 0 points, then dies, their score will not be recorded in the high score board, and the game will think that they got "0" points despite the fact that they got 1,000,000 points. The only way to die without getting points is to use Hyperspace and die on re-entry. Any collision with an enemy will award points and give the player an extra life.


After the success of Defender, there was a successful sequel called Stargate made in 1982, of which 26,000 units were made. After Stargate came Strike Force in 1991. It was one of the first games on WMS's (Bally Midway and Williams Electronics merged in 1986 to form WMS Industries, but kept the Bally, Williams, and Midway labels) new T-Unit arcade hardware.

In 1995, Jeff Minter created Defender 2000 for the Atari Jaguar video game console, published by Williams Electronics.

In 2002, Midway published a 3D remake of Defender for Sony's PS2 video game console as well as the Xbox and GameCube. Also in 2002, Midway published a 2D remake of Defender for the Game Boy Advance. An IGN reviewer said of this game, "I haven't seen a worse classic remake since Atari botched Pac-Man on the 2600 more than two decades ago."

Today there are ports available for several platforms, such as mobile phones.

Later ports of Stargate were relabeled Defender II since Midway no longer had the rights to use the name.

Games inspired by Defender

Defender inspired numerous similar games, including Orbiter, Attack of the Mutant Camels, Repton and Dropzone for 8-bit home computers; Datastorm, Overkill, Star Ray and Guardian for the Amiga, as well as Provocator on the Acorn Archimedes; Eliminator for the TRS-80; and Protector II for the TRS-80 Color Computer and Atari 400/800, Planet Raiders for the TRS-80 Color Computer. It was also the inspiration for Chopper Command for the Atari 2600.

In 1982, Williams Electronics, the pinball division, released a pinball table based upon Defender. The three-flippered table featured drop targets representing colonies and invaders and used all the sounds featured in the arcade coin-op. Coincidentally, many of the pinball tables created at the time by Williams Electronics used the same sound chips.

Ports and platforms

Defender has been ported to most video game consoles of the early 1980s. More recently Defender was included in Midway Arcade Treasures, a compilation available for the GameCube, PS2 and Xbox consoles. Defender was also released on the Xbox Live Arcade for the Xbox 360 in 2006. There is a related 3D shooting game for the same consoles which uses similar sounds but is otherwise not the same game.

Most ports at the time lacked the multiple buttons needed to truly run the game, and so the "reverse" button is often left off and reversals of the joystick direction serve to turn the ship around. This can radically alter the gameplay and make certain strategies impossible on the console ports.

The SAM Coupé version is notable because it was ported in the summer of 1998, before the current retrogaming mania, by one individual, Chris Pile. The conversion was very faithful to the original despite the differences in hardware.

In July 2000, Midway licensed Defender, along with other Williams Electronics games, to Shockwave for use in an online applet to demonstrate the power of their web content platform, entitled Shockwave Arcade Collection. The conversion was created by Digital Eclipse.

In the UK, Acornsoft published an unofficial clone of Defender for the BBC Micro using the original name without permission. After a few months on sale, it was deleted and rereleased as Planetoid (although the game itself was still identical). It was also later released for the Acorn Electron.

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