The Master knows there will be no escape. It is the ultimate victory.
As his power grows, he finds he can sense the Doctor’s presence. He sees into corners of the Doctor’s mind and agitates his neurons, sending his old foe into mad precession around him. He torments the Doctor by degrees, his enemy’s untidy orbit balanced only by a thin veneer of cyclical time—quaint “days” and “nights” that the sentimental fool affixes to his TARDIS’s yawning, infinite maw. The Master laughs at the conceit.
It does not matter, because it cannot last. Inevitably the Doctor’s orbit decays. The Master relishes his enemy’s weakness, thrumming with time-sense and infinite energy as the Doctor supplicates before him, kneeling to touch him, to submit. He grasps at the Doctor’s mind, intent on tearing through memories, but instead he finds himself lingering on the touch of velvet and soft flesh. The sensation builds—lips, teeth and tongue, bodies pressed together in hungering desire, minds a sparking maelstrom surging inexorably toward contact that will never be close enough, never—the Master strains against a prison of flesh and bone as the Doctor cries out, blue eyes wide and guileless in release.
Then there is emptiness, reflected through fingertips on cold stone, and the Master remembers everything. Where. When. How. He screams with the Doctor’s voice, agony cresting in euphoria’s wake, as the remnants of his psyche fall again toward their imprint on the Eye of Harmony.
For that’s all he is, of course. Artron energy, stamped into anti-matter, retains its shape like a scar burnt into flesh. Resonance is inversely proportional to distance. As the Doctor retreats, time and self ebb away in cold fire, and with his last thoughts the Master knows there will be no escape.
It is the ultimate victory.