A character in a story, TV show, movie, etc. that only grows stronger as circumstances get harder so there is never any real chance of losing
The Hulk never loses, he is a win machine, he just gets stronger the angrier he gets until he wins.
(v.) Having the hard work of a group of people completely wasted because of the colossal ineptitude of a single individual or sub-group when the task needs only the slightest effort to complete successfully.
We have a 10 run lead going into the bottom of the ninth. Oh no, they are bringing in this guy from the bullpen? We are about to get valverded and lose 11-10.