Marvel's Iron Man is known for designing and utilizing dozens of different armors throughout his long history, but his two most recent suits could be among his most powerful yet. The Armored Avenger has tangled with the likes of small-time crooks all the way up to Ultron, Thanos and the godlike Korvac, so it's necessary that he would create suits to help him gain an advantage in every fight. His two newest projects are the Celestial Armor and the Cosmic Armor, both making their debuts this year - but which armor would beat the other?
Iron Man, in both comics and the incarnation in the Marvel Cinematic Universe, is known for being prepared against multiple foes, almost to the point of paranoia. He's created armors to fight his friends and fellow Avengers, including the Hulkbuster armor (designed to fight and subdue the Incredible Hulk) and the Thorbuster armor (created specifically to fight Thor, and designed using a combination of Earth science and Asgardian magic). But his Celestial armor blows both previous suits out of the water.
Tony's Celestial armor was built as a precaution. He previously bonded with a Celestial to fight the King in Black during Marvel's 2021 event of the same name. As such, Tony has continued working on a second Celestial armor. It must be noted that the armor also serves to attack the Hulk in his most powerful form: Banner controlling the Hulk like a starship, via a mental "bridge" of sorts, harnessing all of the Hulk's anger without giving up any control to the beast within.
However, the Power Cosmic in the Marvel Universe - which powers Tony's second cosmic suit - is orders of magnitude more powerful than a Celestial. This is known because such power is usually known as the source of Galactus' power, who has battled - and defeated - multiple Celestials whilst wielding the Power Cosmic. In that case, Tony's cosmically-powered suit could easily make short work of his Celestial armor. Granted, Tony does not have the experience with the Power Cosmic that Galactus does, but Tony still has more than enough power to deal with the creators of the Eternals.
It's safe to say that Tony's Power Cosmic-infused suit could absolutely destroy his Celestial armor. Tony's previous armors were quite powerful but neither were on the level of his two latest suits. Iron Man is currently fighting Korvac in the comics, but in many ways, he has already surpassed the villain's power.