->''Defending my planet\\
Is all that I do\\
Hostile intruders\\
Put there by you\\
A mass invasion\\
Coming down from the sky\\
I'll come back fighting\\
Even after I die!\\
-->-- '''Manilla Road''', "Defender"

While it lacks the pop culture legacy of ''VideoGame/PacMan'', ''VideoGame/DonkeyKong'' and ''VideoGame/SpaceInvaders'', ''Defender'', the first game created by Creator/EugeneJarvis and Creator/LarryDeMar (and the second video game by Creator/WilliamsElectronics), is one of the most popular and most relevant video games of the arcade era.

The game's premise is simple: Defend a planet, and its 10 humanoid inhabitants, from abduction by hostile alien spaceships. The difficulty is in the implementation: ''Defender'' presents the player with a dizzying array of controls. The player's ship is controlled with an up-down stick, a thrust button, a fire button, a reverse button to change direction, a smart bomb button that kills all enemies on screen, and an ''VideoGame/{{Asteroids}}''-style hyperspace button. And you have to keep your eye on a [[EnemyDetectingRadar scanner]] that tracks out-of-range enemies.

When the game debuted at the AMOA (Amusement Machine Operators of America) trade show in 1980 which it almost didn't, due to the [=ROMs=] being loaded the wrong way visitors were afraid to go near its complex control panel. Observers decreed that ''Defender'' would fail in the arcades. These same observers thought ''Pac-Man'' was also doomed to failure for being too repetitive. (The critics' darling? ''VideoGame/RallyX''.)

But ''Defender'''s revolutionary side scrolling, cutting-edge 16-color graphics, bold cabinet, fast action, and strong sci-fi storyline compelled arcade patrons to try their hand at its intimidating control panel. Gamers eventually warmed to the difficult controls, and achieved scores the game's creators didn't think were humanly possible.

Why is ''Defender'' historically relevant? Its success proved that even casual gamers could handle complexity. Without ''Defender'', it would have been risky for a company to release an arcade game that challenged the player to manage a joystick and six buttons... which didn't happen again until the first ''VideoGame/StreetFighter'' game in 1987.

The game also received an esoteric sequel, ''Stargate'' (AKA ''Defender II'' nowadays), a PinballSpinoff, a SpiritualSuccessor called ''Strike Force'', a [[UsefulNotes/AtariJaguar Jaguar]] remake titled ''Defender 2000'', as well as a 3-D re-imagining from the early 2000's.

!! This game provides examples of:
* AIBreaker: The Mutant Reverse Line.
* AlienInvasion
* AsteroidsMonster: Swarmer pods.
* AutobotsRockOut: Plop your quarter in and press start? The game gives you an energetic synth guitar to get your juices flowing.
* ColourCodedForYourConvenience: The scanner.
* DifficultySpike: After the first level, the game takes a disproportionate leap in difficulty. Somewhat justified, since it was an arcade game, and it needed to be over at some point so other people could play.
* TheDeterminator: Mutants and Swarmers.
* EarthShatteringKaboom: If all 10 of your humanoids die, your planet explodes, and the game becomes much more difficult -- all the enemy units that would otherwise be relatively docile Landers are instead the much more ornery Mutants. (If you can survive to an attack wave that's divisible by 5, your planet is restored, along with all ten humanoids.) If you're looking for a harder game, [[VideoGameCrueltyPotential you can actually shoot your own humanoids to cause the kaboom.]]
* EnemyDetectingRadar
* FateWorseThanDeath: For the humans, being converted into a Mutant.
* IKnowMortalKombat: ''Joystik'' magazine reported, apparently seriously, that the U.S. Air Force was using ''Defender'' machines to help train its pilots.
* IHaveManyNames: The arcade version of the second game is only called Stargate; most home versions are only called Defender II. The Atari 2600 used both names (Stargate for the first run of cartridges, Defender II for later runs).
* NintendoHard: Not only is ''Defender'' insanely difficult for a first-time player, but after its success, design team Vid Kidz (Creator/EugeneJarvis and Larry De Mar) adopted the attitude that a game should "kick the player's ass" -- their words -- the first time he tries to play it. They applied this philosophy to ''VideoGame/{{Robotron 2084}}'', a classic in its own right.
** ''Stargate'' was even harder (half a dozen new enemies, the namesake in-game gate, ''and'' '''another''' button (inviso) to mind. The game's chapter subtitle in one of the early guide books was "More difficult than flying a 747".
*** Urban legend has it that when the team was working on ''Stargate'', one of the prototype machines was placed in an arcade which - unbeknownst to the designers - was the home of a ''Defender'' champion. So they kept cranking up the difficulty until it could kick ''his'' ass.
* NotTheFallThatKillsYou: Shoot an alien abducting a human and the abductee falls to his death unless you catch him with your ship (or the fall is short enough).
* PlanetLooters: With humans as the resource. If a Lander successfully abducts one, it becomes a dangerous Mutant ship.
** Incidentally, the humans were an afterthought. Earlier versions of the game lacked them, but Jarvis felt that something was missing. Then he realized that the title was meaningless, because there was nothing to defend...
* PinballSpinoff: Appropriately enough, Williams Electronics produced a ''Defender'' [[PhysicalPinballTable arcade pinball machine]]. [[Pinball/{{Defender}} Click here for tropes.]]
** Unsurprisingly, ''Defender'' itself borrowed heavily from Williams' earlier pinball games. Every sound effect in the game was generated by circuits that had been developed for Williams pinball machines.
* PragmaticAdaptation:
** The Atari 2600 version crammed all the controls of the arcade original into a single-button joystick controller, having the player activate a Smart Bomb or use Hyperspace when he went offscreen. That said, it was considered a PortingDisaster.
** However, the 2600 version of Stargate instead used the second controller for smart bombs, Inviso, and hyperspace. (Inviso was up, hyperspace was down, and the button was smart bombs if you had any left, otherwise Inviso if you had that but no smart bombs, otherwise hyperspace). It's generally considered a much improved version all around.
* TheRemake: Remade in 2000 for the [=PS2=], with much more story. And customizable ships.
* SensorSuspense: Oh so very much. The Atari 2600 version of Stargate made it worse, because the blips were all the same color.
* ShownTheirWork: How do you adapt ''Defender'' on the UsefulNotes/Atari2600, which has ONE joystick and ONE button? Pretty well. How do you do the smart bomb? The developers intelligently designed it so that you had to go ''under'' the planet's surface and fire (though that meant you couldn't use it at will in an emergency, you had to prepare). Hyperspace worked the same way, except you had to go off the top of the screen.
* ShoutOut
** The Dynamos split into Space Hums, in a reference to the Music/FrankZappa song Dyna-Moe Humm.
** The Phreds, Big Reds, and Munchers resemble square versions of VideoGame/PacMan.
** See also Take That, below.
* SmartBomb: Arguably the TropeNamer. Definitely the UrExample.
* StalkedByTheBell: The game spawns fast and short (thus elusive) Baiters to hunt down lollygagging players.
* TakeThat / SdrawkcabName: In ''Stargate'', some of the aliens' species are anagrams of Williams' competitors. One of them is called the "Yllabian Space Guppy" (Bally spelled backwards). The alien race as a whole is now called the Irata (Atari backwards).
* TemptingFate: The more humans you land at once, the bigger the bonus. However, if you're killed while holding humans, they automatically turn into Mutants.
* VideoGameRemake: The 2002 [=PS2=] remake was a flight combat game in the vein of Star Fox, with insect-like MechanicalLifeforms‎ called the Manti conquering most of the solar system, and the player character, a rookie soldier named Kyoto, leading the fight to take them down.
* WarpWhistle: The Stargate in the sequel, which transports the player exactly halfway across the planet (or, in this case, the scrolling playfield), or directly to a humanoid if one is being abducted. It can also be used to skip to later levels.
* WrapAround: The playing area is larger than the screen, but if you fly in one direction you'll end up back where you started (as if flying around a planet).
** The wrap-around was exploitable by skilled players, because your ship could cross this invisible boundary, but the aliens could not, so if you crossed the wrap-around point, the aliens would all turn around and head the other way.