World of Warcraft is undoubtedly one of the most influential PC games to date. The massively popular title has been redefining the MMORPG genre since its release in 2004, and still boasts millions of players today. Many staples of video game culture, from the popularization of guilds and raids to the overuse of the word "epic" can be traced back to World of Warcraft's success.

But if returning to the game's roots with World of Warcraft Classic has proven anything, it's that the game has evolved considerably over its 17-year history. Each of WoW's eight expansions have made significant changes, altering players' expectations along the way.

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The Burning Crusade (2007)

The Burning Crusade was the very first expansion for World of Warcraft. In addition to providing a massive influx of content, it also defined what a WoW expansion could be. Blood Elves and Draenei appeared as playable races and the level cap was raised from 60 to 70. TBC also marked the first time that players were able to get their hands on flying mounts, a major turning point for WoW's endgame.

Wrath of the Lich King (2008)

Wrath of the Lich King promotional Art Work

13 years after its release, Wrath of the Lich King is still revered among WoW players as one of its greatest expansions. WotLK was the first expansion to add a new class to the game: the Death Knight. Perhaps even more importantly, Wrath added the Dungeon Finder, marking the first time that World of Warcraft players could use a matchmaking system to tackle dungeons. This feature made a huge portion of WoW's content accessible to more players than ever before, earning the game an army of lifelong fans.

Cataclysm (2010)

Though it was a bit light on massive story beats and explosive raids, Cataclysm marked a major change for World of Warcraft. Azeroth was completely redesigned, as were the leveling experience, questing system, and talent trees. The level cap was raised once again, this time from 80 to 85, and Worgen and Goblins were added to the game as playable races. Cataclysm also marked the first appearance of Transmogrification, allowing players to alter a piece of gear's appearance without changing its stats.

Mists of Pandaria (2012)

Introducing both the Pandaren race and the Monk class, Mists of Pandaria invited numerous comparisons to Kung Fu Panda. The game's fourth expansion added a new continent to explore, as well as Pokemon-inspired Pet Battles. MoP also marked the introduction of raids that could scale in difficulty according to group size.

Warlords of Draenor (2014)

Warlords of Draenor is one of the least popular expansions in WoW's history, doing little to change the core structure of the game. Outside of adding Mythic raids and updating the graphics, WoD's biggest contribution was raising the level cap from 90 to 100. Though the Garrison system was considered underwhelming during its time, its Shipyard component served as a precursor for the mission tables that would become a mainstay in later expansions.

Legion (2016)

Legion introduced the Demon Hunter to World of Warcraft, adding a twelfth playable class to the game. The expansion also marked the first appearance of Mythic Plus Dungeons, which have now become a staple of WoW's endgame content. In addition to raising the level cap to 110, Legion also added class-specific Order Halls, incentivizing players to level up multiple alts.

Battle for Azeroth (2018)

World of Warcraft Battle for Azeroth Expansion Announced

Battle for Azeroth is another of World of Warcraft's least popular expansions, doing little to fundamentally change the game. The expansion's controversial Heart of Azeroth upgrade system tied the power level of most gear to a single necklace, making the endgame loot grind repetitive and unexciting. On the plus side, BfA raised the level cap to 120 and added a slew of unlockable allied races to the game. It also allowed players to opt in or out of PvP using the toggleable War Mode option, eliminating the need for separate PvP and PvE servers.

Shadowlands (2020)

Released in November, Shadowlands has already drastically changed the leveling experience. In addition to implementing a level squish that reduced the max level from 120 to 60, the expansion also added a new starting area to the game. New characters can now level from 1 to 10 in Exile's Reach before playing through one of WoW's previous expansions to level from 10 to 50. Shadowlands also added upgradeable Covenants to the game, combining the best parts of Legion's Order Halls and Warlords of Draenor's Garrisons. With a new patch coming later this year, Shadowlands promises to make even more changes to Blizzard's incredibly popular MMO.

World of Warcraft: Shadowlands is available now on PC.

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