Tony Stark, shrunk to Ant-Man's size, didn't actually take Thanos to the quantum realm but to a place similar to a subspace, essentially his own small space.
He merged Pym particles with the energy of the Space Stone to create a new particle, the basis for developing the Anti-Thanos Armor.
During this process, Tony Stark naturally used the psychic power that he got from the imprint, to create a small subspace miraculously.
This subspace, like the quantum realm, had a significantly different flow of time compared to the outside world.
Although only a short second or two had passed outside, Iron Man had battled Thanos fiercely in this subspace. In the end, he was one move short of defeating Thanos, who held three Infinity Stones.
He had to retreat from the subspace. Unlike the quantum realm, the subspace didn't have the ability to banish others. Its exit was more like a teleportation wormhole of the Cosmic Cube. Both Tony Stark and Thanos could enter and exit it.
So, as soon as Tony emerged, his Anti-Thanos Armor exploded, and Thanos emerged as well.
Although Tony still lost to Thanos, he had caused significant trouble to Thanos. At this point, Thanos was burned on half of his body, leaving deep scars visible to the bone.
Now, he was too injured to use the Reality Stone to heal himself, as player Tony Stark had used the Infinity Stones to leave these wounds. Different Infinity Stones could partially cancel each other's energy, and combined with the erosion of psychic power, Thanos was in a dire situation.
But he still fought on, roaring and charging towards the superheroes in large numbers.
Heroes like Superman, Batman, and Wonder Woman were prepared after hearing Iron Man's warning, and they continued to stand shoulder to shoulder.
After a fierce battle, they finally seized the opportunity to block Thanos. Meanwhile, Mantis and Vision, through Doctor Strange's portal, appeared behind Thanos. Both exerted their full mental control.
They hadn't used this tactic before. Batman had kept it as a trump card, waiting for the right moment.
In the original timeline, Mantis alone could control Thanos, who had collected all four Infinity Stones. Now, Thanos only had three Stones, and Mantis had Vision's assistance, along with Wanda's psychic control ability.
The three of them simultaneously used their powers, aided by physical control from heroes like Superman and Wonder Woman. Thanos couldn't hold on, his struggles weakening.
At this point, Star-Lord chimed in, "Phew, this guy is really not easy to deal with. Wait, let me ask him a question!"
At this moment, Tony Stark was taking care of Captain America, and when he heard this, he gave Star-Lord a stern look. "Hey, don't do anything stupid!"
Peter Quill shrugged, "This time I have no reason to act impulsively. Don't stare at me like that. I did my part in the fight!"
In the recent battle, the spotlight was on other players, Doctor Strange, and others, but Star-Lord didn't slack off. He did his best to create opportunities.
Now that Gamora was still alive and well, Peter Quill didn't have to punch Thanos to wake him from mental control, as it happened in the original timeline.
However, when he suddenly stopped and said he wanted to ask a question, it felt a bit strange.
Bruce Wayne said in a deep voice, "Ask your question after removing the gauntlet."
At this point, Superman and Wonder Woman were pulling off the gauntlet, almost taking it off. Peter Quill raised his hands, "Don't do that. I want to ask him a question, and I'm sure you all are interested too. Hey, Thanos, how did you get the Soul Stone?"
Upon hearing this question, everyone became curious, especially the players who had been participating in the quiz game. They already knew the method of obtaining the Soul Stone from the future videos: a sacrifice of a beloved soul was required.
In the original timeline, Thanos sacrificed Gamora for the Soul Stone. Now that Gamora had escaped her tragic fate, the only possible sacrifice seemed to be Nebula.
Everyone was intrigued, and they were subconsciously thinking about the correct answer due to their participation in the game.
However, when Thanos revealed the truth, it completely surprised them.
"Infinity Stones can actually be obtained on credit... Should I be amazed by the cunningness of this most mysterious stone or the cunningness of Thanos?"
Tony Stark shook his head.
As Thanos confessed this truth, his gauntlet had been pulled off his left hand. Batman immediately opened a portal back to Earth. Tony Stark and Captain America took the Infinity Gauntlet back to Earth and also returned to tend to the injured players.
With all these actions, Thanos was still in a state of controlled stupor. Mantis, Vision, and Scarlet Witch, with their combined mental control, were working exceptionally well.
"Shall we just kill him like this?" Peter Quill aimed his gun at Thanos' head. "It feels like we're letting him off too easily."
Thor raised an eyebrow and lifted his Stormbreaker. "Put away your little water gun. Let me give him a good beheading!"
Just as Thor raised his axe, ready to strike, he suddenly noticed tears in Thanos' eyes...
This cosmic villain who had attempted to wipe out half of the universe's life was shedding tears.
"Haha, turns out this guy isn't as tough as he seems. He's crying out of fear!" Thor chuckled.
"No, he's not afraid or scared right now. He's sorrowful..." Mantis's antennae quivered on her forehead as she said with a strange expression, "He... he's actually feeling sad for us."
At this moment, Thanos' eyes slowly regained clarity, and he looked directly at Thor. With difficulty, he said, "The universe... balance, resources will eventually deplete, countless beings will suffer, some have seen this but don't care... no one has ever tried to change this... After I die, there probably won't be destiny anymore..."
He hadn't finished speaking when Thor swung his axe, beheading Thanos.
Thunk.
The headless corpse fell into a pool of blood. After expending so much effort, they finally defeated this major boss. However, at this moment, everyone looked at each other in silence.