Who said "The cost of heroism is often paid in solitude."?

This quote is attributed to Doctor Strange.

The cost of heroism is often paid in solitude. - Doctor Strange

"The cost of heroism is often paid in solitude."

Doctor Strange Courage

"It's not about how much time you have. It's about how you use it."

"The path to enlightenment is not a destination, but a journey of understanding."

"I am not bound by the laws of nature. I make my own rules."

"Knowledge is power, but wisdom is knowing how to wield it."

"Never let fear stop you from chasing your dreams."

"Courage is being afraid but doing it anyway."

"Sometimes you gotta do what you gotta do."

"Sometimes you have to be the monster to stop the monsters."