Defender

Defender is the hardest of the early arcade classics and the one that invented a lot of what later games took for granted. Eugene Jarvis designed it around a horizontal world wider than the screen, and it was the first game to make the radar scan as important as the playfield.

The world is a strip of terrain that wraps around in both directions, and ten humanoids stand on the surface. Landers descend to capture them; a captured humanoid carried to the top of the screen turns into a mutant that hunts you, and if the last human is taken the entire planet explodes into hunter swarm. The player has a Smart Bomb that clears everything on screen, an Inviso that makes the ship briefly hard to see, and a scanner showing where every lander and mutant is. It is a game about managing several threats at once rather than dodging one thing at a time, and it sold hundreds of thousands of units despite being famously punishing - the manual originally shipped with no explanation, and players learned it from each other.

• ▸A wrapping horizontal world with a scanner radar
• ▸Landers capture humanoids, and lose them all and the planet dies
• ▸Smart Bomb and Inviso as limited-use panic buttons
• ▸Famously steep difficulty curve with no tutorial of any kind