Winner-take-all

You need luck in poker tournaments, because in the nature of this winner-take-all style of play, there will be several occasions when you cannot avoid putting all your money in the pot.

Under winner-take-all elections, many minority candidates find it nearly impossible to win.

[S]he volunteers to take her sister's place at the annual "Hunger Games", a bloody winner-take-all competition in which 24 teens fight to the death.