Infinite Ultron destroyed the multiverse quickly, but not quickly enough, for two reasons.
First, when the Infinity Stones were used across universes, they lost their power to control the "laws" and became nothing more than pure energy sources.
Second, Infinite Ultron was still, fundamentally, a robot. He was inherently different from true intelligent life. With the same six Infinity Stones, Thanos could wipe out half the universe's population with a snap of his fingers, while Ultron only knew how to wage war through brute-force conquest.
The Infinity Stones contained infinite possibilities, but even a single universe held countless living beings. Their combined existence, together with the universe itself, was infinity.
Any individual life-form, limited by its own level of existence, could never achieve true omniscience and omnipotence.
After Oyin broke down the situation of Infinite Ultron's invasion into separate tasks and distributed them to the various departments, the employees of the Multiversal Threat Monitoring Department wore extremely grave expressions.
Dozens of universes had suffered structural damage, Ultron Legions had appeared in over a hundred multiverses, and several universes had already been slaughtered clean by the Ultron Legions.
Although the one who had started this war was not the variant of The One Who Remains they had expected, it was still an exceptionally serious incident.
They needed to provide aid to those universes according to Oyin's instructions.
Harry selected several universes and said to Oyin, "For the universes that have already lost all life, install spacetime bombs directly—you'll do it personally."
As AL, Oyin possessed the ability to replicate and command mechanical life-forms. He had always maintained a mechanical Legion under his command.
"Convert them directly into spacetime energy?"
Harry nodded. "If I'm right, Infinite Ultron should have taken the Infinity Stones from those universes. Blowing them up can weaken him