Donkey Kong’s famed kill screen has been cleared for the first time
If you watched the 2007 documentary King of Kong or followed the controversy surrounding score-chaser Billy Mitchell, you know all about Donkey Kong‘s famous kill screen. For over four decades, no one was able to pass the game’s 117th screen (aka level 22-1) due to a glitch in the game’s bonus timer that kills Mario well before he can reach the top of the stage’s girders.
That was true until last weekend, when Mario speedrunner Kosmic shared the news that he had passed the kill screen using a combination of frame-perfect emulator inputs, a well-known ladder movement glitch, and a bit of luck. And even though Kosmic’s trick is functionally impossible to pull off with human reflexes on real hardware, the method shows how the game’s seemingly insurmountable kill screen actually can be overcome without modifying the code on an official Donkey Kong arcade board.
Breaking the broken ladder
Donkey Kong‘s kill screen is a side effect of the limited 8-bit register the game uses when calculating the two largest digits of a level’s Bonus Timer (which doubles as the overall timer for each screen). At level 22, this calculation makes the register overflow past 256 and back down to 4, giving Mario just a few seconds to complete the stage before instant death.
