Sentinels are definitely LONG overdue, especially for those of us who were first exposed to marvel in the 80s and 90s ('90s x-men cartoon anyone!
Those seekers could be a bit nasty when overleveled, though they do make lots of charged tiles that the ai is too dumb to collect. Still, aoe goons are always a threat if ignored, and they definitely target thorkoye teams by pulling the lowest health character out front.
Eliminators seem a lot less threatening, though they do put out damage fast. So maybe thugs are the best analogy?
Overall, not quite as complex as aim so far, but a welcome addition to a game with so much repetitive grinding.
Anyone else have thoughts?
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I hope we get a playable Sentinel here soon
Or a Sentinel-themed Boss Event.
Featuring Sinister? Master Mold? Nimrod? Onslaught?
More slow goons.
The Sentinel Seekers create a charged tile every turn. That’s worse than the Sentry Fighters, who have a condition that stops their tile destruction. But the Seekers will probably cause less cascades, since they aren’t destroying tiles every turn, only when there are enough charged tiles.
Or they can turn MODOK into a Sentinel and make that into a PVE that leads into a Boss Event 
It’s fun to speculate as to what the Sentinels might possibly do. Personally I’d rather wait to get a formal announcement so we know when they are coming into the game…