vendetta - A blood feud in which the family of a murdered person seeks vengeance on the murderer or the murderer's family
As the final act of his vendetta against Rugen, Inigo pulled out his sword and said, "Hello. My name is Inigo Montoya. You killed my father. Prepare to die."
enthusiastic - Feeling or showing a great deal of excitement and interest about somebody or something.
Bill was enthusiastic about baseball, went to baseball games as often as he could, and spent hours each day learning about baseball players and teams.