I also showed an alternate reality with Runaways that was much closer to 616 in which, once again, the time bubbles were suggested (and why should anyone who doesn't really know much about Kang suggest he can make time bubbles if its not standard knowledge? That wouldn't even make sense). Again, since Kang is not based in 616, alternate versions that are reliable (I agree that the FF one is sillier than the Runaways one for example) and close to the Kang we know, could be used.
There is a Scarlett Centurion that is Kang, and another one that is his son Marcus (I won't hold it to you since Kang's chronology is pretty much shit).
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I thought Doom had a time machine in his suit but someone told me he didn't, hence my comment. Still, it isn't as if Kang couldn't send him to "Alioth" time and the fact Doom is a time traveller would doom him (pun intended). Again, my take is that Doom wins because of magic, it seems just a lot easier to do, and I'm quite aware of Kang's suckiness against magic.