The Dementors that had been drifting around above the Castle had vanished.
An enraged Headmaster Dumbledore had driven every last one of them out of the Castle, and Su Er reached the Whomping Willow without any trouble.
It gently stretched its branches, occasionally giving a shudder, looking like a lion lazily licking its paws after a hunt.
As Su Er approached, the Whomping Willow sensed an unfamiliar presence drawing near and suddenly began flailing wildly. Its branches whipped through the air, seemingly warning the stranger away.
"Oh." Su Er let out a soft exclamation and took a step back. A willow branch sliced through the air and lashed hard against the muddy ground a short distance ahead.
Clods of earth, still damp from the recently stopped rain, immediately went flying.
A warning lash!
Ordinary young wizards would generally have chosen to retreat at that point, because the Whomping Willow certainly looked intimidating now.
But Su Er was different. He knew exactly what the Whomping Willow's weakness was-a knot on its trunk, hidden behind its branches.
It just took a little finesse to avoid the flying branches and touch that knot.
It was simple. A single piece of Transfiguration would do the job.
Su Er had no desire to be strung up and whipped by the Whomping Willow. If magic could solve the problem easily, why not use it?
There were plenty of things near the Whomping Willow that could be used for Transfiguration. Soon, two cats transfigured from stones bounded into its attack range.
One was slightly larger, tasked with attracting the Whomping Willow's attention. It leaped about, weaving between the flying branches. A tree was a tree, after all; ultimately, it could not outwit a clever young wizard.
The other was slightly smaller, meant to slip deeper inside and