Skirmish in the Forbidden Forest

"You filthy half-breeds! You have been given the right to stay here by Cornelius Fudge!"

- Umbridge

The Skirmish in the Forbidden Forest was a battle that took place in the Forbidden Forest on the grounds of Hogwarts School of Witchcraft and Wizardry.

Background
Umbridge caught Harry trying to use the Floo Network in her office, and he and his friends and fellow D.A. members Hermione Granger, Ron and Ginny Weasley, Neville Longbottom, and Luna Lovegood were held in her office by Inquisitorial Squad members. When Harry refused to tell her what he had been doing, Umbridge first attempted to dose him with Veritaserum, but Professor Snape told her he had no more. She then claimed that the Cruciatus Curse might "loosen his tongue". Hermione then spoke up, and tricked Umbridge into following her and Harry into the Forbidden Forest in search of an alleged "secret weapon" of the Order of the Phoenix.

The Skirmish
In the forest, Umbridge was confronted by a herd of centaurs, whom she shamelessly insulted with racial slurs and her wizarding arrogance. Umbridge then attacked one of the centaurs near her. She was chased and nearly killed by them. Although she survived, her wand was snapped in half when one of the centaurs stepped on it.

Rescue
Umbridge was ultimately rescued by Dumbledore, although she was apparently left with a significant fear of centaurs afterwards, reacting violently at even the sound of hoofbeats. How Dumbledore managed to rescue her from the human-hating centaurs without suffering any injury himself remained a mystery, though it is likely that centaurs had respect for Albus, based on their salute at his funeral.