As defined by Urban Dictionary:
Magnificent Bastard -
There's a certain type of character that defies such definitions as hero or villain, good or evil, friend or enemy. Love him or loathe him, you have to admire him. And at the end of the day, there's only one thing we can call him... a Magnificent Bastard.
The Magnificent Bastard is intelligent, capable, supremely competent, and always in control. He can be playing everyone from both ends, or making it up as he goes along with such consummate skill he gets away with it. He might be cynically exploiting all around him for his own ends, or persuading everyone to do everything for him. He might be a lying sneaky bastard playing everyone for his own selfish ends, but he goes about it with such breathtaking skill and panache you admire him for it. Above all else, what defines a Magnificent Bastard is his ability to evoke not just amazement, but grudging admiration, from friend, foe and audience alike.