Within the context of Classic, the method most frequently proposed is to re-tune bosses to make them harder. Rather than copying the numbers, re-create the relative difficulty. Kind of like, when you first start working out, you use small weights. When you get stronger, you lift bigger weights. The WoW community is more knowledgeable, more experienced, has better hardware, etc. We're "stronger." So give us tougher bosses. There are a lot of forms that could take. Bosses were constantly re-tuned during vanilla anyway, so if Ragnaros does 10% more damage or something, is that really a problem? I don't think it is. What about resistance gear? back in the day, collecting resist gear was a thing people did. But the numbers and strategies are so well known today that only the tank really needs it anymore. Bosses could be re-tuned with more resistible elemental damage so that's important for entire raids to gear appropriately. That would be entirely keeping with the spirit of vanilla even if the actually numbers sitting in a database somewhere were different than they were ~13 years ago. If you want to go a little farther, a few people have proposed adding new abilities to old bosses, adjusting their timing, etc.
Other methods have been discussed. For example, mods could be crippled. DBM didn't exist back then, and the other boss that did that I don't remember the name of, didn't do as much back then as DBM does now. If our goal is to recreate the experience as it was, then obviously not having DBM would be a reasonable way to accomplish that. DBM simply existing, makes the game today easier than it was. So disallow it. Again, this is completely consistent with the spirit of vanilla. Remember one-button-decursing? That was nerfed. They crippled the capabilities of the modding API to disallow that because it made the game too easy. So what if they cripple it a little bit more to once again make the game less easy?
Allied Races Overview Everything about Allied Races, new playable races in World of Warcraft: Battle for Azeroth, including unlock requirements for each race, Heritage Armor, customization options, and speculation when they are playable. Battle for Azeroth (110-120) Leveling Tips and Consumables How to level from 110 to 120 as quickly as possible in WoW Battle for Azeroth, including recommended zone order, best consumables, general leveling tips, and best addons. Azerite Armor Overview and FAQ Everything known about Azerite Armor and Azerite Traits in Battle for Azeroth including what Heart of Azeroth Level they unlock and how to respec them using an Azerite Reforger. The Battle for Lordaeron - Introductory Battle for Azeroth Quests This guide is an overview of the Battle for Lordaeron scenario, including a walkthrough from both Alliance and Horde points of view. Wowhead's Guide on How to Play World of Warcraft The basics of getting started in World of Warcraft as a brand-new player. Game installation, character creation, how to move, and complete your first quest.