It seems unlikely that this doesn't already have a thread, but I was unable to find either here or in the Sentinels main forum.
So - Scions! Beings in the thrall of OblivAeon, with a strong hint that at least one of them is someone we've seen before. I'm actually going to guess that MOST of them are existing characters, since OblivAeon thusfar has shown a strong theme of reusing existing characters. I'd bet on one being a hero, most others as existing villains, with maybe an Enviroment target.
Let's start with the one we've sort-of seen. A familiar voice, who mocks the heroes as "not qute as dense" as they seem. It gets familiar with them, using names over codenames, and says it was "outside of space and time," and that whilst it's a jerk, it doesn't want to destroy everything.
It's Miss Information. She knows personal information on the heroes, would ally with a greater power instead of fightng to the last, and would then manipulate the situation. She could never hide her contempt.
Other characters I could picture as Scions would mostly be villains with a space or "cosmic" theme who we've not seen either in this event or in the future - since the human mind adores symmetry, let's also bank on one from each non-Vengeance expansion, since that's how the villains-turned-hero worked. My picks would be Voss, Spite, Apostate, and The Dreamer. The Dreamer seems least certain - that could be Kismet, instead, but (1) leaving Dreamer in there keeps the count at five villains whilst still having a hero on the team, and (2) Kismet was fan-created. Drawing from Environment decks, Zhu Long and Jansa Vi Dero both seem like intriguing options to me, but ultimately unlikely.
Well Miss Information would likely still have a vendetta against the FF team so she would be out in my mind, Voss is lost to the mists so I think it's unlikely he would be one but plausible, Spite is quite dead, Apostate works for the Host so I find it unlikely he would be swayed towards OblivAeon, and the Dreamer seems more likely to be someone fighting the event directly.
Just FYI, Miss Information was also fan-created. (She was the runner-up in that Create a Villain contest.) I don't think that's really a barrier to her being tied in to the main story line like that.
Like, I don't know any properties of the Mist which would convince me that getting something out of it would be harder than reaching "beyond space and time". No one knows anything about The Host. Spite is probably dead, sure, but so was Omnitron before getting remade.
The Dreamer might not be the one, sure. As I said, I'm less sure about her. Of course, if the heroes are going to put a second mentally ill child on the frontlines, that doesn't sit right with me - but that's my own hangup, rather than a prediction of the plot.
I have two seperate theories on the Scions. However, first it should be noted that the Art Stream today confirmed a character called Aeon Master as a Scion (looks like the Aeon men we've been seeing) and that Progeny is also a Scion. Adam also said the number of Scions is between 2 and 50 but indicated 50 was a really high ceiling.
Progeny being a Scion kicks my one theory pretty hard, because I was basing them on off Progeny's Scion cards (Blight, Storm, Frost and Flame).
My other theory is that they might be based on the 4 Horsemen (Plague, Death, War and Famine if memory serves). Mostly because I remember Apocalypse creating his 4 horsemen in X-men and I see a little Apocalypse in OblivAeon.
If I had to guess and actual number though... 5 Scion decks I think.
Possible other Scions: Voss because we know we are supposed to see him again and his style fits with a War type setting. I also like Kaagra Warfang as a Scion, she made a deal with something for the Colessium and her Bloodsworn, could be OblivAeon and she also fits the feel of this massive force of powerful beings well.
I think Apostate working for the Host means he will not be picked up by OblivAeon. Miss Info is possible, but she's shown as kind of losing her mind and while OblivAeon was resonsibe for driving Infinitor insane I don't think he'd make someone like that a Scion, more of a minion.
OblivAeon showed interest in Omnitrn before, could he re-recreate him?
I"m positive he was joking, but since we saw two before the end of the day I'm certain we have a minimum of 4-5 in reality. I doubt there will actually be more than 10, that's just too many villain decks and it is indicated that each scion might have it's own villain deck. Of course, I'm assuming a lot since we don't know how OblivAeon plays
Spite is dead twice over. His dead body was taken over by Gloomweaver and we don't have the Spites until Tactics which is after this event. Spite also only cares for death so being helpful at all would not be his MO