In its 22 years since launch, WoW has gradually accumulated an elaborate ecosystem of metrics and simulation tools allowing players to analyze and optimize their combat performance. That ecosystem grew so elaborate, in fact, that Blizzard ultimately opted—with somewhat mixed results—to restrict how much combat data community developers could access so the studio can design encounters around the capabilities of its players and not their addons.But according to former WoW designer Wyatt Cheng, not even Blizzard had a good way to know what peak player performance data looked like in the MMO's early days. In a YouTube short, Cheng said designing vanilla WoW raid bosses in the absence of comprehensive player combat data required the tried-and-true method of manually grinding training dummies. And then rounding up. Just to be safe.Cheng outlined the design process for Patchwerk, the flesh golem boss added as part of the Naxxramas raid in June 2006. Patchwerk, Cheng said, was inspired by ex-Blizzard director Jeff Kaplan's fondness for the Avatar of War raid boss in Everquest—an encounter that was, essentially, just a test of fundamentals."As Jeff remembered it, [Avatar of War] wasn't too fancy. It just hit you really hard," Cheng said. "Tanks tanking, healers healing, DPS doing their thing—all the excitement of the Avatar of War was based on how tightly it was tuned. And he had a theory that a boss like that in World of Warcraft could be really exciting, too."Cheng added a little bit of variety to that core concept, designing Patchwerk to alternate his attacks between main tanks and off tanks to keep healers on their toes. Unfortunately, that produced an issue: It incentivized raid groups to trivialize the fight by stacking as many healers as possible and slowly whittling away Patchwerk's health bar.Thus, the Enrage timer was born. Patchwerk, Cheng said, "was the first time we used an Enrage timer as an explicit DPS check." Players had to take Patchwerk down before a fixed amount of time passed or he'd start pumping out lethal damage and wipe the group—a mechanic that's now a fixture of WoW boss design.The Enrage mechanic, however, introduced another complication: To know how much boss-killing time to give players, you have to know how much damage they're capable of. And Blizzard, well, didn't."Back in those days, there just wasn't robust data on how much DPS a player could realistically put out. This was before World of Logs," Cheng said, referencing an early, now-defunct destination for WoW analytics that's been followed by generations of successors.Without a corpus of player combat data, Blizzard worked out its DPS threshold with some manual number collection and a bit of napkin math."We had top players in the company test every single class against target dummies to try and put out as much damage as possible," Cheng said. "And then, because we knew that serious raiders always find clever ways to push the game to its limits, we padded Patchwerk's health by an extra 30%, just for good measure."Evidently, Blizzard's estimate was on the mark. Surviving threads from 2006 have raiders describing Patchwerk as "a pure mathematical gearcheck": punishing if your raid group's gear or DPS was lacking, but straightforward if you could keep the pace.2006 was a simpler time—but I'm sure Blizzard has built their own tools for simulating the necessary metrics in the years since. For their sake, if not ours. 2026 games: All the upcoming gamesBest PC games: Our all-time favoritesFree PC games: Freebie festBest FPS games: Finest gunplayBest RPGs: Grand adventuresBest co-op games: Better together