Robotack 2024

Eugene Jarvis, co-creator of Robotron 2084, once declared: "The only legitimate use of a computer is to play games." Sir Clive Sinclair, creator of the ZX81, held a rather different view. As portrayed in the film Micro Men, Sinclair famously lamented: "Everywhere I go, games! This is what my lifetime of achievement has been reduced to! Clive Sinclair, the man who brought you Jet Set fucking Willy!" He'd built machines for education and serious computing, only to watch the public obsess over jumping things. Well, Don Crawford & Dave Spinnett (D&D) have spent the past four years proving Eugene Jarvis right—by cramming a Robotron-inspired shooter onto your beloved ZX81, a machine with 1K of RAM that was never meant to do anything this ridiculous.

ROBOTACK 2024 is a high-resolution graphics game for the ZX81/Timex Sinclair 1000, best played via the EightyOne emulator in ZXPand mode with a joystick. On actual hardware it works too, assuming you've got the ZXPand connected and nerves of steel. The game theoretically offers 99 rounds, though the creators admit it gets "pretty quick" after round 8, challenging anyone to break that barrier. This follows their 2021 debut entry, Zonkey Kong, a game that took them 38 years to complete. ROBOTACK only took four years by comparison—a blistering pace.

The ZX81's ULA (Uncommitted Logic Array) is legendary for its limitations. The machine was designed to display chunky text characters, not detailed graphics—making high-resolution games a near-impossible feat requiring serious compromise and sacrifice. D&D spent four years wrestling with these constraints, modifying graphical elements to capture Robotron's spirit whilst keeping the game playable on hardware that struggles to display anything beyond BASIC listings. The result blends Robotron's relentless robot hordes with shooting mechanics borrowed from Berzerk: you shoot in the direction you're moving, controlled with a single joystick rather than Robotron's twin-stick arcade setup.

The enemies are faithful homages: Grunts swarm you in packs, Electrodes are passive deadly mines—easily shot but frustrating when you carelessly bump into one whilst being chased (they turn white and vanish when destroyed), Hulks (appearing from round 2) are massively armored juggernauts that cannot be killed but can be pushed back with sustained fire, saving humans from a crushing death whilst clearing paths through the horde. Tanks (round 5 onwards) fire bouncing projectiles that ricochet off walls—and unlike the arcade original, you can't destroy the shots, only dodge them. The sound effects attempt to replicate Robotron's glorious cacophony, making firefights genuinely thrilling as you hold down that fire button and unleash rapid-fire carnage. Score management matters: you earn an extra life every 10,000 points, rewarding aggressive human rescue and robot destruction.

Strategy is paramount. Movement: Stay in corners and avoid the middle whenever possible, though some waves make this impossible. Diagonals are your friends—you move slightly faster diagonally, and Grunts are slower to catch you. Combat: Keep that fire button pushed at all times for rapid fire. When surrounded, practice sitting still and firing in all directions to clear an escape route—you don't always need to move to survive. Learn to shoot diagonally; it's a lifesaver. Human rescue: Grab those civilians, but only when you're safe—points escalate for each rescue, just like the original. Enemy behaviour: Grunts collect together whilst chasing you and hide behind civilians. Your shots don't harm humans but will kill Grunts hiding behind them, so keep firing even when you think the coast is clear.

It's deliberately brutal. Four years of wrestling the ZX81's ULA, learning obscure programming tricks, pulling hair out over hardware limitations, and tapping into an active online community to solve impossible problems. The payoff is a genuinely playable high-resolution action game running on a machine Sir Clive designed for teaching BASIC to schoolchildren. It's not flawless—the compromises are visible, the difficulty is punishing—but it works, it's thrilling, and it proves Eugene Jarvis right. The only legitimate use of a computer is to play games. Eugene Jarvis would be proud. Sir Clive would be furious. We're delighted.