Lord Balrama, I would say.
Jai Hari. I fully agree with mr prasad. Even bhima and duryodhana acknowledged Lord Balrams greatness and went for training under him. What makes Shri Balram a very unique personality is that in the entire mahabharata he is the only person who can confidently say that the kauravas and pandavas are equally dear to him. When Bhima hit the foul blow on duryodhanas thigh he repramanded bhima and was all set to punish him although bhima had a blood relation with him ( Kunti was a sister of Vasudeva Balramjis father ) and duryodhana was not related to him in any way. he was a man who valued principles more than relation ships.
Balrama and Hanumaan