Thing is, in my opinion, if Blizzard leads it to Sargeras' death, people will be satisfied unless they add some really strange plot twists that go the wrong way.
"I was a normal baby for 30 seconds, then ninjas stole my mamma" - Deadpool
"so what do we do?" "well jack, you stand there and say 'gee rocket raccoon I'm so glad you brought that Unfeasibly large cannon with you..' and i go like this BRAKKA BRAKKA BRAKKA" - Rocket Raccoon
Yeah, the guy in the other topic just "magically" guessed the exact name of the expansion. Yeah, totally fake. That guy clearly doesn't know what he's talking about!!
To me where it all gets to be a bit questionable is Grom being the main villain. I mean we just had a expansion where a hellscream was the last boss now we are going to have another? That sounds a bit fishy to me. Yeah i could see grom being in it if it is indeed time traveling/fixing what someone has done to change the past. However i cant see him being the final bad guy it would just be Hellscream 2.0.......well i guess 1.0? see fucking time travel! Tho granted Grom is far more of a bad ass then his son.
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A lot of people were mad about MoP, but they got over it or quit.
I think if the next one IS about Legion, the community wont take it as harshly as the MoP announcement.
I mean, how silly did pandas sound? At least with Legion, there is a pointer to it (Wrathion and a few other things I cant really remember)