Rookie Moves by peu_a_peu [E, 75k]
“He was absorbed in his little object permanence experiments when something incandescent and impossibly large exploded toward him.
At first Harry thought the door had flown open and admitted the moon. But he could see through the gargantuan shape to the still-shut door; it was translucent and shimmering with magic. The bright mass resolved before him as he backed away from it.
It was over a meter across, scaled, spiky, pinning him with eyes as big as quaffles: a dragon’s head, attached to a long neck that went right through the door. A life-sized dragon, he realized, composed of silvery light, so enormous that only the head was in the room with him.
There could be no confusion on whose this was.
“I knew a Patronus would work!” Harry exclaimed. “Jesus, it’s huge!”
“You’ll say that again before the day’s out,” came Malfoy’s voice from the dragon’s enormous maw.”
“You can hear me?” Harry asked, half-expecting Malfoy’s blond head to pop out from between the rows of glossy fangs. “How are you doing that?”
“I’m excellent at charms, nitwit!”
“And yet this one eluded you for the longest time,” Harry said, smiling giddily as the full implication sank in. “You must have an exceptionally powerful, exceptionally happy new memory to fuel it.”
The dragon’s great face betrayed nothing. “I don’t think we’re at all far apart, I’ve still got the tail in here with me. I’ll pull it back and you follow.”
The dragon began to shrink back; Harry dived through it, receiving a dose of minty invigoration, and pulled open the door so he could keep it in view as it slithered backward down the corridor, losing size. He pulled open another door, maddeningly identical, as the now-hubcap-sized dragon’s head phased through it, and caught a last puff of smoke as its snout slipped back into Malfoy’s wand.
“Hello again,” Harry said, spreading his arms wide. “It’s me, your wellspring of happiness.”