Diablo speedrunners searched 2.2 billion random dungeon seeds to debunk a two-decade old speedrun record – Rock Paper Shotgun
When you said “stay a while”…A team of Diablo speedrunners spent months searching the 1996 RPG’s 2.2 billion valid randomly generated dungeon seeds to find the layout used in a stupidly lucky speedrun they suspected to be illegitimate, says a new report from Ars Technica’s Kyle Orland.The three minute, 12 second sorcerer run by Maciej “Groobo” Maselewski was first uploaded to Speed Demos Archive in 2009. Watching it “feels like watching someone win the lottery,” writes Orland, thanks to a seemingly random streak of entrance and exit stairways right next to each other, allowing for a rapid, safe descent through the dungeon. Groobo lucked out again on the ninth floor, nabbing the Naj’s Puzzler item needed for later teleporting exploits.Beginning “in earnest last February”, a team of tool assisted Diablo speedrunners started trying to recreate the run, using their own custom map generation tool built by “reverse-engineering a disassembled Diablo executable”. From Ars:That tool can take any of the game’s billions of possible random seeds and quickly determine the map layout, item distribution, and quest placement available in the generated save file. A scanner built on top of that tool can then quickly look through those generated dungeons for ones that might be optimal for speedrunning.The team’s initial goal here was just to learn from Groobo’s run, both for their own speedrunning and as a test case to make sure the scanner worked. The problem? The seed they were looking for didn’t actually exist. Groobo had, in other words, made up the whole thing. “We just had a lot of curiosity and resentment that drove us to dig even deeper,” a runner named Staphen told Ars. “Betrayal might be another way to describe it,” added team member AJenbo. “To find out that this had been done illegitimately… and the person had both gotten and taken a lot of praise for their achievement.”From Ars:In their effort to find Groobo’s storied run (or at least one that resembled it), the TAS team conducted a distributed search across the game’s roughly 2.2 billion valid RNG seeds. Each of these seeds represents a different specific second on the system clock when a Diablo save file is created, ranging from between January 1, 1970, and December 31, 2038 (the only valid dates accepted by the game).After comparisons failed to turn up a re-creation of Groobo’s dungeon containing the level 9 Naj’s Puzzler drop, they began to search “impossible seeds” – “which could only be created by using save modification tools to force a creation date after the year 2038”. They eventually found dungeons with the drop in the right place, using seeds for the years 2056 and 2074.They also discovered that the original speedrun video had been spliced together from multiple different runs. “In the end we only found two levels that had come from the same run so at least 13 (probably 15) runs were spliced into one video, which is a lot for a game with just 16 levels,” AJenbo told Ars.Other evidence (some of it quite glaring in hindsight) began to pile up afterwards, but do read Ars Technica’s full piece for that. Why go to all this trouble for a 27 year old speedrun? “It did harm,” speedrunner Cecil told Ars. “Groobo’s alleged cheating in 2009 completely stopped interest in speedrunning this category [of Diablo]. No one tried, no one could.”If that’s all left you feeling exhausted at the lurking deception inherent in men’s souls, Here’s a free Diablo-inspired indie where you play as the mayor of Tristam – an upstanding chap by all counts.
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