Which Atari game’s accessory integration do you feel was the most innovative for its time?

[killamch89]

Atari pioneered accessory integration early on, but which implementation truly impressed you most? The XE joystick port allowed plug-and-play peripherals that expanded input beyond the standard joystick. The Atari 2600 Steering Wheel controller for racing games introduced analog control decades before modern titles. Equally groundbreaking was the Atari 5200’s numeric keypad for game-specific overlays, shaping titles like Star Raiders. Which Atari accessory integration do you consider the most innovative for its era, and how did it enhance gameplay?