Buckbeak is Rubeus Hagrid's pet Hippogriff who Harry Potter rode on the back of. He was later sentenced to death for hurting Draco Malfoys arm so Harry along with this two best friends Ron Weasley, and Hermione Granger decided to rescue him along with Sirius Black from the Ministry of Magic.
Harry Potter and the Prisoner of Azkaban
In 1993, Rubeus Hagrid brought his first Care of Magical Creatures class to see and study Buckbeak, as well as other hippogriffs. Under Hagrid's direction, Harry was able to successfully approach Buckbeak and was even allowed to ride him for a short flight around the paddock.
As hippogriffs are immensely proud creatures, Buckbeak was offended when Draco Malfoy insulted him. This resulted in him injuring the boy's arm. Draco's father, Lucius Malfoy insisted that the Hippogriff be put to death. Malfoy's influence in the Ministry of Magic led to his views being the majority vote, and the execution was to be carried out. Walden Macnair came to the Hogwarts as the employed executioner, and Buckbeak was tied in Hagrid's pumpkin patch to await his death.
However, using a Time-Turner, Harry Potter and Hermione Granger rescued Buckbeak just prior to the execution. Originally, they had heard the swish of an axe and assumed Buckbeak had been killed. Later, as it became evident that Buckbeak had escaped, Macnair swung his axe into a pumpkin in anger. When Harry and Hermione were about to be attacked by Remus Lupin in his werewolf form, Buckbeak saved them by attacking him and scaring him off. Buckbeak was used to get to Professor Flitwick's Office which Sirius was locked in, enabling Sirius to escape the Dementors and leave Hogwarts.
Order of the Phoenix
Other Wizards & Witches
Hogwarts School of Witchcraft and Wizardry