More Steven Universe spoilers! Assuming Shatterbird is constrained by the Manton effect, I doubt the S9 (except maybe the Siberian) have enough firepower to even scratch the Diamonds, the things Blue tanked were insane, and I doubt Yellow’s durability is any worse. Even if they only have their hot bods, it’ll still be like fighting 2 even more durable Crawlers (though with admitedly lesser regeneration), rather than Fenja and Menja.
Ehh. I’d imagine Shatterbird and maybe Crawler could top the stuff Blue was hit with tenfold or more. That includes Steven’s bubble attack, which was the only non-barn attack that really fazed Blue in the sequence where the CGs fly past, attacking one by one. (Symbolism, only a diamond can scratch a diamond.)
You’re right, the Diamonds are probably significantly more durable than Fenja and Menja, but I do think you’re overestimating the attacks we’ve seen them at the receiving end of.
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