Originally Posted by
WolfRider
Since WoW's launch, Blizzard writes the next expansion's big lines before the actual expac last patch.
But sometimes they are listening too much for the players' hype or sometimes they are a little bit clumsy.
Vanilla : introducing Azeroth, Races, Factions conflicts, Fire Elemental Lord, Old Gods influences over creatures (Nagas, Quiraji), Titans legacy, Black Dragonlight. Last patch : Naxxramas. Should have been followed by Wrath of the Lich King but too much Illidan's hype and "we want blood elves".
Burning Crusade : introducing a destroyed Draenor (Outland), two new race (Blood Elves and Draeneis) that involved a retcon over the Lost ones, Archimonde,Kil'Jaeden and Sargeras story, introducing Naarus, Arrakoas, and some other races. Giving a small hint on Illidan's activities, but end with the SunWell story and Kil'Jaeden. This expansion has no direct relation with the next but contains interesting story, hints and fills some blanks for the future Legion expansion.
Wrath of the Lich King : Could have been the real first Expansion, but would be less written and less interesting. It develops Dragonflights, Titans' legacy, Old Gods influences, Arthas is a commercial argument but he totally drives the story. Introducing Garrosh in a new perspective and development for futures expansions. Ending Arthas' story. Last patch is about a new dragonflight threatening others, a link to the next expansion.
Cataclysm : From a player's perspective this is a reboot, new questlines from lvl1 to 60, introducing new races (Worgens and Goblins), bringing back factions conflicts on the low leveling, and elemental lords on the HL quests, ending Deathwing story. Garrosh has a really important sidestory development in lowlevel quests and in the last HL zone. This expansion introduces new Titans' legacy and Old Gods' influences
Mists of Pandaria : The Factions' conflict is foreground, on a new land were actions and feelings have a direct impact. Introducing new Titans' legacy, Old Gods' influences and Wrathion, a son of the fallen Deathwing, who's gathering heroes against a Legion's future invasion. This expansion develops a conflict into the Hord, leading to the final patch where Garrosh's gone too much hardcore on the Hord and a real danger. The last patch also introduces a sidestory where Wrathion and Kairosdormu, a bronze dragon, are looking for a time artifact. This expansion stored some paths to the next expansion, but too much offgame stories and not enough ingame immersion seemed too clumsy.
Warlords of Draenor : Blizzard wrote a prequel story to the expansion : Garrosh, who's got stoped in his crazy Hord takeover, has been jailed and judged but escaped with Wrathion and Kairosdormu's help. They wanted him to gather an army by traveling through portals to many alternative Draenors, but Garrosh had another plan in mind. He killed Kairos and told his alternate father, Grommash Hellscream to not accept Gul'dan's offer. He helped him to gather the orcs clans and form the Iron Hord. The expansion starts with Iron Hord's invasion on Azeroth at the Dark Portal. We enter Alternative Draenor, free the captives Shadows' council members led by Gul'dan and find allies on Draenor. We fight back the Iron Hord, we end Garrosh' story, Gul'dan takes over Grommash.
Last patch : the Iron Hord's remains are empowered by Gul'dan's gift, the blood of Mannoroth. We fight the last orcs in the Tanaan jungle and the threatening Fel Hord in the last raid. Leads to the death of Archimonde and Gul'dan's exile into the Twisting Neither.
If Blizzard told you that you would fight a Fel Hord from the beginning, it would spoil the plot and the next expansion. They can't do that directly, but from WoD's beginning, there were a lot of hints : Gul'dan's freedom, the fact that whatever you tried, the end would not change (in this case, Gul'dan will go to the Tomb of Sargeras).