Even though a modern server architecture is used, Classic servers won't have the same features that current World of Warcraft does. There won't be cross-realm servers or Looking For Raid and Dungeon Finder automatic party matchmaking. There are still a lot of questions about how the team will tackle it. This endeavor is being undertaken by an entirely separate team at Blizzard from the one working on World of Warcraft and its next expansion.
For some weird reason Warlock used to be underrepresented in vanilla WoW. However, the least popular doesn’t mean that they were bad. Warlocks had amazing damage and some truly unique utility abilities allowing them to summon players or create Healthstones for the whole group. Similarly to Hunters, Warlocks were amazing for solo players with the ability to summon various demons to help them.
Similarly to Alliance’s Paladin, Shaman is a unique class option for Horde. Shaman boasts amazing group utility with its strong buffs through totems. Windfury totem is a must in any raid while Bloodlust in Classic is unique to the Shaman class. Restoration Shamans were considered the best group healers while other specs were also amazing in PvP environment capable of dishing out insane burst damage. Additionally, Shamans were able to wear mail armor, so any piece with spell power on mail set piece was almost certainly yours.
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