Some people want 1.12, others don't. The target market for WoW Classic is much bigger than just people who play on private servers. It includes people that played WoW vanilla back in the day and have long since stopped playing at all, and people who started after vanilla and never got to experience it, and completely new people that are just wanting to try WoW Classic because it's so hyped and such an important part of video game history, etc.
My assumption is that they will create a single version that combines elements from the various vanilla patches (and some newer ideas). The main thing that I'd be interested in understanding is whether they will try to build on an old client version from vanilla or a modern client. The server side is the easy thing (as shown by the various open source WoW servers) since they already have all the content, scripting and databases from vanilla.
Pretty much, I don't see them putting out a 1.0 AND a 1.12 together so they'll have to pick one and maybe expand upon it later depending on how it is received. It sure won't be an easy choice and no matter which they pick there will be blowback from the Vanilla community.
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Well there is some missing data that is mostly historically accurate mob damage/hps and the like but I think getting as close as possible will be fine. But you make some good points, the target audience is a wide scope of players, former players and even prospective players. It is why I'm curious what directions they take and how they decide to do it.
Just bug fixes and exploits,
I was watching a steam last night and the streamer said he wants absolutely everything the same, including that old bug were you loot and get stuck crouching in the loot position. To me that is absolutely utter nonsense, having that won't make any difference to the Vanilla experience.
He's one of those players that won't play it, but he's so butthurt about fact that others might have fun, he wants players to have as miserable experience as possible. He's a douche and should be ignored.
Its ongoing theme on this forum. Many are shitposting nonsense, while having absolutely no interest in classic servers. It will probably be like that too on official forums because people who get access to it are ones playing retail, not players who are interested in classic. Because of those assholes there might be problems with developers communication.