Claudius is power hungry. With the birth of a male heri, Hamlet, and the younger brother of Hamlet, Sr., he had no real chance to sit on the throne of Denmark as king. So, his ambition makes his take matters into his own hands. Notice that poison is a motif that runs throughout the play. Claudius is the first to use poison by ouring it into the ear of his royal brother as he sleeps in his orchard. This method presents no tangible foul play, so he seems innocent until the ghost reveals his plot. He then secures assess to the throne by marrying his sister-in-law, the present Queen Gertrude. He is willing to kill again to maintain his title. He is responsible for the deaths of Hamlet and Gertrude via poison. Even after Laertes points the blame on Claudius in public, Claudius weakly asks for his friends of Denmark to defend him. He is dobly killed by Hamlet finally with the poisoned sword and drink.