Stephen was not stupid. On the contrary, he was incredibly intelligent. While not on par with world-class figures like Tony Stark or Reed Richards, he was certainly among the most brilliant minds of his generation.
So when Stephen's astral form witnessed the Ancient One's soul depart from her body, guided by a cosmic phantom seemingly composed of the stars themselves, he thought deeply and made several important decisions. With the Ancient One's death, he would inevitably become the new Sorcerer Supreme. However, before that moment arrived, he was completely alone.
Sebastian immediately sensed the departure of his old friend through their mystical connection. Instead of sadness, he felt genuine joy and profound relief. After so many years of struggle and servitude to the Vishanti, his old friend had finally broken free of her constraints. She was like a fish swimming freely in the boundless sea or a bird soaring through infinite skies.
Now Sebastian needed to focus entirely on preparing his final plan.
Everyone else had already entered their respective battlefields. Sebastian needed to seize this final opportunity and fight with everything he had. Success or failure would be decided today.
Above the Hong Kong Sanctum's location, or rather above the ruins of what had been the Hong Kong Sanctum, a bizarre dimension filled with darkness and despair descended from above. It surged downward upon the city below. The Dark Dimension seemed intent on utterly engulfing Earth.
At this moment, Karl Mordo stood in the city streets watching as the Dark Dimension finally broke through the defenses of the Kamar-Taj Sanctums and descended upon Earth. He excitedly shouted toward the descending darkness, "My Lord, you have finally arrived! Let Earth be completely embraced by your eternal darkness!"
As Mordo shouted these words, he prepared to leap into the air to embrace the descending Dark Dimension.
But at that precise moment, several red beams of light shot from behind Mordo. They struck him directly and blasted him away with tremendous force. His back was completely mangled. The flesh and bone were exposed horrifically.
Lying on the ground in agony, Mordo stared in disbelief at Kaecilius and the other Hogwarts wizards. His voice was hoarse as he growled through the pain, "What are you doing? You clearly released the great Lord Dormammu. Why did you ambush me? I understand now. You want to take all the credit for yourselves, you damned bastards!"
Without answering Mordo's accusations, Sebastian suddenly appeared beside Kaecilius and the others through Apparition. Mordo's expression upon seeing Sebastian's arrival was like a duck with its neck being choked. He was unable to utter another word.
Nodding to Kaecilius and the others, Sebastian waved his hand and opened a portal to Hogwarts. He said to Kaecilius and the gathered teachers, "Hogwarts has been attacked while we were occupied here. Although we have reinforcements defending the school, we are still short-handed against the assault. As the Vice-Headmaster of Hogwarts, Kaecilius, you will return to oversee things in my place. Leave the matters here to me."
Hearing Sebastian's words, the other Hogwarts teachers immediately returned through the portal. After quickly assessing the battle situation, they joined the other Hogwarts teachers, outstanding students, and mutant allies who were fighting against Thanos's invading army. They began their counterattack immediately.
At this moment, Kaecilius looked at Sebastian and whispered with concern, "Headmaster Sebastian, the Dark Dimension has arrived above us. Are you absolutely sure there will not be any problems?"
"Do not worry. There will not be any problems. Whether I succeed or not, the Dark Dimension cannot truly descend upon Earth," Sebastian said with absolute confidence.
Kaecilius pursed his lips and asked again, "Then what about you, Headmaster Sebastian? What are you going to do?"
"Kaecilius, you should know that if I want to continue forward, I have to do this. This is my only real chance. Besides, those beings are not planning to give me any other chances, are they? If I ultimately succeed, then naturally there is nothing more to say. But if I fail, Hogwarts will have to rely on you to lead it. With Tony Stark and the others taking care of you, you should not have too much of a problem," Sebastian explained.
"But..." Kaecilius began to protest.
Sebastian waved his hand, stopping Kaecilius from speaking further. With a flick of his wrist, his wand materialized in his hand. He cast the Patronus Charm directly at the dark power descending from above. A white mist of brilliant light transformed into a massive shield. It blocked the invasion of the dark power temporarily. Only then did Sebastian say to Kaecilius, "Things have come to this point and cannot be changed now. There is no point in saying more. Go back to Hogwarts now!"
With a deep sigh, Kaecilius said no more. He nodded respectfully to Sebastian, then turned and walked into the portal. He left this place and returned to Hogwarts to fulfill his duty.