Blizzard EntertainmentAfter careful consideration, we decided on Patch 1.12: Drums of War as our foundation, because it represents the most complete version of the classic experience
Blizzard EntertainmentAfter stitching various key pieces together, we had a locally rebuilt version of Patch 1.12 running internally.
Blizzard EntertainmentOur initial runs exposed a few (expected) issues: the game sometimes crashed, didn’t recognize our modern video cards, and was incompatible with our current login system.
Blizzard EntertainmentSo we asked ourselves, would it still be possible to deliver an authentic classic experience if we took our modern code, with all its back-end improvements and changes, and used it to process the Patch 1.12 game data? While that might seem counterintuitive, this would inherently include classic systems like skill ranks, old quests and terrain, talents, and so on, while later features like Transmog and Achievements would effectively not exist because they were entirely absent from the data.
Blizzard EntertainmentAdditional improvements will include modern anti-cheat/botting detection, customer service and Battle.net integration, and similar conveniences that do not affect the core gameplay experience.