It is the Burning Crusade Classic: These are the main stages
One of the most memorable aspects of The Burning Crusade, the first WoW expansion, was that it introduced Draenei and Blood Elves to playable races. They were added to the Classic variant through a pre-patch. After that, the actual expansion starts.
The contents from TBC Classic were unlocked in five phases, following this order:
The first phase: Karazhan, Gruul, Magtheridon
2. Serpentshrine, Fortress of Sturme
Phase 3: Hyjal Peak, Black Temple, Arena Season 2
Phase 4: Zul’Aman, Arena Season 3
Phase 5: Sunwell Plateau, Quel’Danas, Terrace of Magisters, Arena Season 4
Kenner in the game Ur-Spiel falls, and thereby the Classic edition plays more slowly than the original version, as all the content and including (and comprising) Hyjalgipfel, was available at the time before the publication of The Burning Crusade. The result of this type of time gap should ensure that speedy gamers will have more fun playing TBC Classic since they cannot complete the entire content (like the well-known guns) in the fastest duration.