To The Rescue.
Dumbledore strode into the forest at a brisk pace. Stepping on twigs and brambles, but making no noise. The forest was as silent as though somebody had cast 'Muffliato' over it. His cloak swished and the sparks which his wand emitted illuminated his face, unsmiling and resolute. Dumbledore inserted his hand into the folds of his cloak. Out came the 'Delluminator'. For the first time in hours, the shadow of a smile crossed his face. The Delluminator... His own creation. Brings light at a click. But also saps light at a click. You cannot have light unless you steal it from another place... He smiled at the idea. But, now was not the time to admire his creations. He replaced it back in his pocket, his fingers searching for something else... As they closed around a smooth, round object, he nodded, as though assuring himself that it was still there. He became grim again. It was a reminder of what had been done, what still remained to be done...
He had reached a clearing. He could hear voices; angry, sneering voices. He extracted his hand from his robes and stepped into the clearing... A herd of angry centaurs was grouped around what seemed to be a heap of clothes on the ground. "Filthy half breeds we are, are we, you lump of dragon dung...?" one of them was saying. He kicked the mass on the ground with his hoof. It shuddered and let out a pitiable whimper.
"BANE..." said Dumbledore. His voice was low, but nevertheless echoed all around the clearing. The centaur that had just kicked the heap, turned around. His eyes caught sight of Dumbledore, and he let out a barely muffled cry of surprise. "Dumbledore" he said, after he had somewhat recovered from the shock of seeing him there, "I was not expecting to see you here. What is it that you want? Another teacher from our herd...?"
There was a mutinous murmur from the herd, some of the centaurs dug the ground with their hooves and tossed their heads in anger...
"It is clear what I want, Bane..." said Dumbledore coolly. He looked at the quivering lump at Bane's feet, with a hint of disgust. "I have come here to claim Prof Umbridge, you have no right to keep her here. She belongs at Hogwarts..."
"She does, does she?" growled Bane. He galloped towards Dumbledore, stopping just inches from him; his breath warm on the latter's face. Dumbledore stood his ground. "Yes, she does", he said softly. Bane let out a yell of frustration. "You are insane, Dumbledore... Yes you are. This maggot has been plotting your downfall, and yet you are here to 'help' her? You are eccentric..." He let out a frustrated snort.
As the centaur neighed in exasperation, Umbridge let out a shriek of fear and fainted.
"'Help' has always been given, and will always be offered, at Hogwarts to those who ask for it..." said Dumbledore.
He spoke each syllable softly, but Bane reacted as if Dumbledore had slapped him. The temperature dropped and all sound eliminated as though someone had clamped a lid on the clearing. Dumbledore's hair was whipped by a wind which came from nowhere, his cloak swished, and when he spoke, it was as if he'd used 'Sonorus' to magnify his voice, "I EXPECT YOU ALL TO LEAVE THIS PLACE, AT ONCE... I WILL NOT REPEAT MYSELF, YOU MUST OBLIGE TO MY REQUEST." His eyes flashed...
Dumbledore had not raised his wand, but the centaurs glanced once at it and within the blink of an eye, they turned tail and galloped away.
Dumbledore glanced at the unconscious figure of Umbridge for a second time, with hatred burning in his eyes, and aimed his wand at her... Immediately, she floated into the air as though lifted onto an invisible stretcher.
The wizard put his hand into the pocket of his robe for the last time, and extracted something small... He held his fist in the wandlight, his arm outstretched in front of him. Slowly, his fingers parted to reveal a quaint Snitch. As it sat on his palm, golden against his white flesh, it fluttered its wings feebly. He gazed unseeingly at the Snitch, lost in thought, the tiny golden orb reflected in his eyes. As his fingers closed back around the ball, the headmaster had made up his mind... It was time.