YMMV / What If…? S1E8 "What If… Ultron Won?"

• Ass Pull: Thanos somehow managing to get the rest of the Infinity Stones. As noted on the main page, the sequence of events that led to Thanos claiming the stones would not have matched up with the canon up till that point (Gamora still being alive despite the fact that Thanos would have needed her to know where the Soul Stone is and get it, Asgard and Xandar still being intact,^note Surtur destroyed the former during Thor: Ragnarok while Thanos attacked the latter right before the start of Infinity War to obtain the Power Stone no word of Thanos being on Earth before despite the fact that he would’ve needed to come to the planet to collect the Time Stone, etc…) While it can be justified due to multiverse theory, some felt it was just a contrived way for Ultron to get the rest of the Infinity Stones as quickly as possible.
• Complete Monster: Infinity Ultron is a much viler variant of Ultron who successfully managed to upload himself into Vision's body. Deciding "peace" means the eradication of all life, Ultron wipes out all of humanity with a nuclear apocalypse. Ultron then kills Thanos, loots the Infinity Stones from his body, and uses their reality-warping power to systematically annihilate all other life in the universe. After finishing that goal, Ultron recognizes the existence of the Multiverse itself and, armed with the Infinity Stones, attempts to completely purge every single universe of life.
• Crosses the Line Twice: Ultron vs. Thanos sounds at best like an epic fight the MCU has never seen, or at worst horrifying. In truth? Ultron one-shots and bisects him, with only a moment of confusion from him before splitting apart, and it happens so fast it veers into outright Black Comedy.
• Memetic Mutation: They killed Tony Stark again!^explanation Tony Stark in all of his episodes featuring him is consistently killed. Here in particular, he's shown facing his demise at the hands of Ultron who obtained what would have been Vision's body, igniting that joke again.
• Questionable Casting: While most of the recasted characters for this show have been accepted by fans, Ross Marquand as Ultron has proven to be a little more contentious. Mostly, it's due to the fact that his voice bears little resemblance to James Spader's take on the character from Age of Ultron, a performance that was going to be a Tough Act to Follow regardless.
• Shocking Moments: Ultron becomes the most dangerous character in the MCU to date, easily wiping out his entire universe, then noticing Uatu's existence, which motivates him to annihilate all life in the multiverse. The internet went abuzz over how powerful Ultron was, with scenes such as him effortlessly blowing up whole planets, taking a bite out of a galaxy, and rupturing the space-time continuum with his punches being especially discussed.

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