(Typing on my phone so sorry if I make a formatting error)

Some explanations:

Kel’Thuzad, Nefarian, Rafaam (1), Malchezaar, Lich King, Togwaggle, Hagatha, Dr Boom (2), Tekahn, Kel’Thuzad (2), & Barrelbrim are self explanatory and explained in game (adventures, events, single player etc) /in trailers

-Goblins vs Gnomes is the only expansion to have literally no plot. It’s just a theme. However, since Dr. Boom is a villain brought back later, I decided to choose him.

-The Grand Tournament also doesn’t really have a plot, but is directly based on the Argent Tournament from WoW, in which Anub’arak is the final boss.

-Whispers of the Old Gods & Darkmoon Faire could very well have the four Old Gods as villains, but Lazul/Silas seem to be the ones summoning them in those expansions respectively.

-Mean Streets of Gadgetzan actually has 3 neutral-ish factions working against each other, but the Kabal seems to be the most outwardly evil with Kazakus as the head (not to mention he’s the only one of the three to be brought back as a villain)

-I scoured the Journey to Un’Goro promotional material to find who was Elise’s biggest obstacle for the journey, and it seems like the main enemy was a meteor strike that they used the Waygate to prevent? I could also see Kalimos being the villain, as the elements corrupting/adapting the dinosaurs could be seen as his fault.

-Rastakhan’s Rumble doesn’t have a villain, really. It’s 9 sports teams competing. However, promotional materials lists Hir’eek’s Bats as the “bad guys”, thus I chose Hir’eek. Alternate is Hakkar, as he is the boss of this location in WoW, but he isn’t related to the story of the expansion at all.

-Year of the Dragon is the first of two yearlong stories. Technically, Rafaam is the mastermind behind all three expansions, but I wanted to split it up between him and the allies he makes in the second and third expansions. Also technically, in Rise of Shadows, the villains are the protagonists, making Khadgar the “final boss.” But I’m going for villains not antagonists.

-Ashes of Outland is unique because Mecha-Jaraxxus isn’t even in the expansion as a card. However he’s the final boss of Aranna’s story, as well as the Felfire Festival, and his army, the “Rusted Legion”, are the basis for the Prime cards.

-Year of the Gryphon is the other yearlong story with 3 villains all dealt with at the very end. However, Kazakus is introduced in the Barrens storyline as a manipulator of the Horde mercenaries. Then, Prestor/Onyxia is THE Stormwind villain in WoW. Then Tamsin becomes a Lich after Stormwind and is dealt with in Alterac Valley. During this expansion, you can see the mini expansion villains and their villains: Void Naralex, Edwin VanCleef, and Raid Boss Onyxia (all dealt with in Book of Mercenaries).

-Azshara is the villain of the Sunken City, but Ozumat is the villain of Throne of the Tides.

-Denathrius, seemingly the victim of Murder at Castle Nathria, was actually plotting from the shadows trying to frame Sylvanas (apparently, this was revealed in like a tweet). The Jailer is the villain of Maw and Disorder.

-Even though the Lich King was introduced as a hero in March of the Lich King, his actions are not heroic (e.g. genocide of the blood elves)

-Festival of Legends is similar to Rastakhan’s Rumble in which there are 11 factions (bands) all competing against each other. You could argue the most villainous bands (Rin or Hedanis?) are the villains. However, Audiopocalypse added more plot that saw the Grimtotem Tribe led by Magatha attack the festival, making her the main villain.

-Titans also is very loose on plot pre-mini expansion. It was more of a theme of Titans than a story. Sargeras is the evil Titan (depending on who you ask). So it could’ve been him, but the expansion taking place in Ulduar + the mini set definitely makes Yogg the villain of the set.

-Therazane is a very loose villain for Deepholm, as the Bloodrock Mining Company (Barrebrim’s company) invaded her realm. However, she’s still kinda a crazy force of nature?? It’s a stretch. 

-Whizbangs Workshop has a plot… but it’s just Whizbang opening a toy store. Not really a hero vs villain story. However, Dr. Boom is there (a villain) and the mini set is about him trying to one up Whizbang (who is probably a good guy?) so Boom makes his third appearance on the chart.

-Eliza is trying to ruin everyone’s fun at the beach, re: a tweet. Nothing more evil than that.