The Ancient One was the Sorcerer Supreme and leader of the Masters of the Mystic Arts. A woman of Celtic origins, the Ancient One discovered the ways of the mystic arts and vowed to use them to protect the Earth from threats invisible to human eyes and incomprehensible to ordinary minds. Soon, she began helping others and eventually trained many to become a Master of the Mystic Arts.
However, not everyone agreed with her and one of her students, Kaecilius, and a few others challenged her and went rogue. As time passed by, she was then discovered by Stephen Strange, who was seeking to cure his crippled hands. Sensing a kind of ambition that was similar to Kaecilius, the Ancient One was at first reluctant to allow him into the sanctuary, but was convinced by Karl Mordo to allow him to learn the mystic arts.
When Kaecilius and Dormammu's threat loomed, she was finally killed by her former apprentice, but not before giving advice to Stephen as to how to defeat Dormammu and his followers and asking him to consider the purposes his powers had for him before passing away from her wounds.
Battle vs. Rahm Kota (by Monkey Doctor 33)
A bar in London
"That all you got, son?" A man puts down a glass of liquor on the table, a whole host of empty bottles scattered near the glass.
"Sir, I... uh, I, think we just ran out of drinks for everyone," the bartender says with a tone of wariness. Behind him lies a large empty cabinet devoid of any beverages. The man literally finished the bar's entire roster of drinks within 45 minutes but nobody bothered him. Why? Nobody knows what dangles on his back or who he is. He was complaining about a 'Galactic Empire' of sorts, but everybody knows that Star Wars isn't real. Perhaps he's just a lunatic, but then he looks very battle-worn and wears something of a military attire.
"That's all you have? (Sigh) Go to Earth, they say. Taste all their joys, they say. Get lots of drinks and forget the war, they say. I swear Nar Shaddaa was better than this hole."
"Do you plan on paying for all your expenses, sir?" The bartender asks while putting away a few bottles.
"You accept credits, boy?" The man asks while examining a bottle half-consciously, trying to figure out the ingredients of the drink that failed to satisfy him. He needs something to drown him in his sorrows after what could've been his biggest failure in his own war.