Heero asked Quatre to bring Wing Zero to him because it is faster for him to get on it right away. After Heero got onto his Gundam, he encountered Wufei. At this time, Wufei was beginning to have doubt toward the true meaning of justice. He felt that it didn't make sense in that he was still fighting and involved in a war while everything was at peace (when there's peace, there're no need for warrriors nor wars and Wufei was getting very confused about the very purpose of his involvement).
After having fought a indecisive but intense battle with Heero. Heero asked Wufei, "Are you sure you still want to fight?" When Wufei did not reply, Heero remarked, "Do you still want to fight? Do you still want us to be the tragic warriors that we are? Do you still want us to go against each other and turn everything upside down?" Heero then said, "How many more people do I still have to kill before I can finally stop?" Then, Heero shut off his engine and replied, "I don't know anymore...You tell me, Wufei." And with those words, Heero fell back into Earth into the ocean with his gundam, leaving behind him, a very shocked Wufei.
Meanwhile, Marimeia turned the military base into an underground command center. Zechs and Noin were battling the enemies (250 Mobile Suits) on ground and they were losing. Fortunately, Duo, Quatre and Trowa arrived in time. Each of the gundam made its own appearance in a dramatic way.
Despite the fact that having the gundams around made the battle more to their advantage, it was not long before all five of them ran out of ammunitions, but thankfully, Heero arrived in the nick of time, using his laser beam gun and attack the underground command center. Dekim Barton, however, threatened Heero saying that he had Relena with him as hostage but Heero made no move to surrender or stop his shooting. Relena didn't say nor do anything either, because she believed in and trusted Heero. And under the assault of Heero's gundam, the underground command base was finaly destroyed. And it was at this time that Lady Une rushed out and tried to protect both Relena and Marimeia.
At the end, Marimeia lost because Heero destroyed her fortress, in which she has thought to be impossible. At this crucial moment, Lady Une came to protect Mariemaia and Relena, saying that even though Terize's child is wrong, people should still forgive her mistake. She also pointed out that it is the old man who was with Marimeia that was the one who really wanted to control the Earth and the colonies. The old man Lady Une was mentioning about had been shot by someone else. Before he got shot, the old man tried to shoot Relena, but Marimeia protected her and got injured in the process. After Marimeia was injured, Heero came in and said to her: I can makes you feel confortable (He PRETENDED to kill her). But the gun was already out of bullets (Heero knew that also). He then said "I don't have to kill anybody anymore" (At this point, he was thinking of the girl who was killed because he had messed up one of his mission- see OVA 1). After saying these words, Heero fainted and Relena ran to him and holding him tightly and lovingly in her arms and said, "It's all right, all over, Heero....."
At the very end, Duo destroyed Trowa's, Quatre's, and his own Gundam after he said, "It's really over." Duo ended up working somewhere fixing (or picking) at some things and Hirde ran to him and hugged him, in which he smiled in return. Trowa went back to Cathrine who is looking at him lovingly because he was alive. Quatre went to the space cleaning the wreckage (??), staying with his men and his followers. Wufei went back to China and also destroyed his Gundam. His last words to Nataku was, "You can rest now, Nataku." Then Sally showed up and asked, "Do you want to work with me??" in which he agreed to.
Relena was giving a lecture on the stage while, Heero was on the second floor watching Relena for a very long period . His Gundam was destroyed as a result of using too much energy on destroying the fortress.
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