__________________ "Happiness is a lie. Life is horror. The light is always dying all across the universe. The last star will flicker out someday, when it does, all that remains is shadow. And I will be its king!"'-Amahl Farouk
I don't think Ultron can put Steppenwolf down. He simply isn't strong enough.
On the other hand, Ultron is supposed to be extremely durable. Can Steppenwolf cleave Ultron with such might that it replicates what a combined blast from Thor/Vision/Iron Man did?
I would lean towards yes for now, because Vision's beam alone was keeping Ultron down - so all three may not have been necessary.
As a side question - should the beams have been able to hurt Ultron going by Vibranium in the comics? Seems it should be tougher than that.
Well, IIRC, Tony referred to Ultron as using a "vibranium cocktail" on his final form, which implies his body likely wasn't 100% pure vibranium. And we've also seen vibranium get messed up by certain sonic frequencies in Black Panther, Vision's vibranium/organic blend body pierced and head get cracked open like an egg in Infinity War and Cap's shield get broken by Thanos in Endgame, so MCU vibranium clearly has limits to how much it can take.
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