What is the dark side of Arjuna in Mahabharata?

What is the dark side of Arjuna in Mahabharata? I don’t think Arjuna has any dark side in the Mahabharata. Dark side means something remotely evil which you are hiding from most people. I don’t know anything about Arjuna as such. Yes, he did have weaknesses after all he was a human. One weakness was his undaunted loyalty to his elder brother Yudhishthir. It is not wrong to follow elder brother; it is your dharma to respect him but sometimes things go overboard and cross limits (example - dice game incident), then you should also break open the bounds and do whatever you can do to prevent the adharma about to happen or what you are witnessing. Arjuna couldn’t do anything then. In this case, Bhima was better than him in this aspect as, he had warned to burn Yudhishthira’s hands if he played further. He immediately spoke up and was ready to fill the whole court with blood by his merciless arms, but stopped by Arjun again. I think, that this was the weakness Arjuna had. Although he vents out his anger on Yudhishthira on 17th day of War, he could have taken some action earlier. Other than this, I couldn’t find any weakness of his. Arjuna was a man who symbolised courage, dedication, warrior skill, determination, love as well as friendship of the highest order (Krishn-Arjun). This is what he teaches us in the entire epic and this weakness of his should be taken as lesson.