Full powered Kuurth was written to be absolutely unstoppable in every way possible. The only thing that bothered him was his entire body inside and out was lit of fire and even then he was just like ARRGGG ANNOYING!! continued on his way...
Thanos has alot of showings so its hard to compare with a guy in one arc granted he was uber.
Anyway I think they have comparable durability, but nod to thanos because it has been shown he tanked crazier stuff (not saying kuurth can't just saying Thanos has more showings of things above)
Then what exactly happened in that scene? All I remember was Magneto crushing and malforming Kuurth's helmet causing Kuurth to toss his hammer at Mags.
I could be wrong, but it seemed like it to me if he yelled at Mags as his helmet was being crushed, and felt threatened enough to attack Mags directly. Although the helmet did regen its shape afterwards.
I haven't seen anything Kuurth has done that puts him over Thanos in terms of durability, except for the highly subjective hype of him being "truly invulnernable", which can easily spiral into no limits fallacies.
He wasn't screaming/yelling the whole time, but he was speaking gibberish. I don't know what he was saying, but usually if someone screams (even if its gibberish) in response to their helmet crushing into their head, it gives the impression that they're being hurt by it. But I guess the scene can be subjective, much like the extent of Kuurth's invulnerability hype.
By the way Kuurth was portrayed in FI I'd choose him there were several pages with plans to stop him and a lot of stuff off panel and he didn't even slow down or flinched.
Except Colossanauts first showing that was the only plot way to take Kuurth out.
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