From 6:00 to 6:35 in the Blizzcon 2010 Warcraft Quest & Lore Panel
About Kil'jaeden & Burning Legion
"But in the end of the day, you know, we pretty much smashed his head back down the toilet ball, you know what I mean, at the Sunwell."
"So his gonna be dealing with total different emotions at this point, right."
"He wanted to eredicate all life before, and it wasn't really personal."
"Now it's personal."
"We will likely see him ... again!"
26:22 "We will absolutely go back and effect Outland."
Keep in mind that we have had 3 consecutive expansions that has been in Azeroth.
Wrath of the Lich King (Northrend \ Azeroth), Cataclysm (Azeroth), Mists of Pandaria (Pandaria \ Azeroth).
It's much more fun to discuss if you find something they said at Blizzcon Quest & Lore Panel video,
using what they say as an argument for what you believe in.
So if you have something you believe in, you need to quote something they said and back up with a video,
to make us believe that, that may be a possibility, right.
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I just think it's interesting to see what they said so many years ago, and I feel it's increasing the likely chance of what been said back then, to be happening next as it's been a while plus 3 consecutive expansions that has been set primarly in Azeroth.