The concept of pressing a button to lock onto an enemy or object is now regarded as something of a standard in video games.
But in 1998, Zelda: Ocarina of Time was the first game to offer the system.
How did this invention come about? At a theme park, according to the game's general director, Toru Osawa.
"We thought if we went there, we might get some ideas. We got our boss's approval, and Koizumi-san, Ikeda-san and I went. It sure was a hot summer!" Osawa recalled in the latest Iwata Asks.
"We ducked into a playhouse to cool off. They were doing a ninja show. A number of ninja were surrounding the main samurai and one lashed out with a kusarigama (sickle-and-chain). The lead samurai caught it with his left arm, the chain stretched tight, and the ninja moved in a circle around him."
Pressing the N64 controller's Z Button keeps the game's camera and Link's movement focused, allowing for accurate targeting even from a distance. On the 3DS, the L button is used to similar effect.
The group of developers observed how in the scripted stage show a single samurai was able to defeat a group of attacking ninjas, as each attacked one at a time.
This one-on-one fighting style was then implemented in Ocarina of Time, along with the lock-on mechanics of the Z-targeting.