Yeah, minor comic spoilers ahead.
This is my selection of some moments that we most likely will not see in the Amazon series, either due to copyright restrictions or because they simply would no longer fit.
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Claire Bono.
Debbies first friend after Omni-man attemp to take over the world.She also is the wife of the super-hero known as Super-Patriot.
Since Super-Patriot may be won´t fit in the Amazon tv show, Claire is most likely to be out too.
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Fusion kid & Alien Worldwide invasion.
In the comic series, a sudden alien invasion occurs on a global scale, this takes place within Brit side comic and one Invincible Issue, also ties-in demonstrating the inefficiency of the Guardians of the Globe team and even the GDA in the face of space threats.Even as a reason for this, Invincible is sent on space missions.
There was nothing the characters could do to prevent the damage caused to Earth, this is handled by a minor character from Brit side comic.
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Invincible along side Capes Inc. members
I hope I´m wrong here and Cecil run into Capes inc when they are needed, but best case scenario we only get to see Kid Thor, who appears in almost all the side-comics.Captain Capitalism and Bolt are much minor characters.
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‘Kirkman-verse’ heroes team-up vs Omnipotus.
May be Omnipotus will fit in the TV show as an antagonist or minor villain, but Tech-Jacket, Brit, and lot of Capes Incorporated won´t fit in the Amazon TV show.
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Shapesmith debut.
Again, in the comic series Shapesmith debuts defeating solo the Lizard League and saving a prision break, it seems like he will fight the Lizard League but also in the TV show but will meet the Guardians of the Globe in another way.
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Invincible & Marvel team up.
Don´t seem like Invincible from Amazon will crossover with Marvel.It is a shame, because this is the only Invincible comic series crossover with another universe.