He was named for his preferred form of torture
He had a battle going on with the Ottomans by 1462 and had ascended to the Wallachian throne. Vlad gave his men orders to poison wells and set crops on fire because the enemy forces were three times as large as his own. Additionally, he hired sick people to infiltrate and infect the opposition.
His victims were frequently decapitated, skinned, and/or cooked alive. However, impalement eventually became his preferred method of execution, in large part because it was a type of pain. Impaling entailed inserting a stick into the victim's genitalia and their mouth, shoulders, or neck. The victim would frequently not pass away for several hours or even days.
He tortured both domestic and foreign adversaries, and his reputation grew as a result. According to one story, he reportedly ate while surrounded by a "forest" of spikes covered in writhing bodies. Vlad Tepes (also known as "Vlad the Impaler") was known for his fondness for impaling his foes and then leaving them to die.