The Mad Titan MCU villain who he has largely ignored: Ultron. Interestingly enough, the MCU has actually delved more into their potential conflict than the comics have, albeit very briefly. However, comics fans deserve to see these two incredible villains clash as well, especially given how well they complement each other.
Thanos’ ideology is one of his most defining features. An ardent irer of Death, he wants to kill all life in the universe as a gift to her. Most other villains in the Marvel Universe don’t want to annihilate all life in the universe, and so Thanos has come into conflict with many of them over his long history. This applies to many MCU villains as well, with his forces coming into conflict with Ronan the Acc, another intergalactic warlord. Loki has even killed Thanos in an alternate timeline. However, Thanos has surprisingly not actually come into major conflict with the villain who is the ultimate anathema to his goals.
In The Thing #6 written by Walter Mosley and pencilled by Tom Reilly, the Thing and Doctor Doom forces against Death’s Netherworld army, using robots to fight against them. These robots are effective against Death as they are non-living, which means that Death has no power over them. This revelation implies that Death would also not be able to control the robotic villain Ultron or any of his drone army. As such, Thanos would never be able to include them in his ultimate gift to Death.
In addition to being undying himself, Ultron’s mission also runs counter to Thanos’ ultimate goals. Ultron’s newest form “Ultron Pym,” a combination of Ultron and his creator Hank Pym, is obsessed with fusing humans and robots together into cyborgs. While the human element of the cyborg does die soon after being merged, the robotic half will still simulate its consciousness. So while the creation of these cyborgs could deliver a life form to Death, it is almost a mockery of her, as the living half still appears to live on. If Thanos encountered Ultron Pym’s creations, he would likely be shocked and furious at their implications and at how they essentially represent life forms unable to be added to his ultimate tribute to Death.
While a version of Ultron and Thanos did briefly interact in the MCU television series What If…?, they have somewhat surprisingly not interacted in the comics. This is especially strange given that Ultron has clashed with major villains like Kang, whom he fought repeatedly in the apocalyptic Ultron War. If these two ultimate MCU villains ever do come into conflict with each other, it will surely be Thanos’ toughest battle in the Marvel Universe yet, as Ultron represents both his ultimate obstacle and the one thing he despises most.
