This is a page not only about the rules of Sudden Death, but also about the Achievement: win in Sudden Death.
Sudden Death happens right after normal play. If the game is a tie after the minute of play given at the beginning the game goes into Sudden Death. The rules of Sudden Death are simple: the first person that scores first wins. However, during Sudden Death, the players cannot gain Power Shots. If a player already has a Power Shot at the end of regulation, then it will carry over, but during Sudden Death the Power Bar does not become full meaning that you won't get any more Power Shots after Sudden Death. Once a player scores the game is immediately over, and the player that scored wins the game. There is currently no time limit to Sudden Death. In all the Game Modes there are Sudden Death, except of the Head Cup Poules. Here matches can end in draws.
The best way to do this is to try to go ahead by one goal. Then try to keep the ball out of either team's goal. If your opponent scores on your goal then score back so that you are ahead by one. If they accidentally score an own goal, then allow them to score so that you are up by one. Then with just under ten seconds left let them score again tying the game. That way they should definitely be able to score before the game ends, but there won't be enough time for any more goals. Also try to save your Power Shot, because your opponent most likely won't have a Power Shot to block with meaning that you have a free shot on goal.
An other variant is, to jump over your opponent before the ball comes down (use costumes to boost your jump) and pushing him into your goal. Activate power when your bar is full. Just before the regular time ends, let him out, so that his Power Shot won't finish before the time ends. Then you have two Power Shots, he only one. Use France, Germany, Netherlands, Croatia or Luxembourg best, their shots mostly end in a goal.
Unlock Requirements with Sudden Death. Edit
Asura: Win against Asura without Powershot, without conceding a single goal, with 10 goal difference by Sudden Death and win 10 times.
Pluto: Win against Pluto without Powershot, without conceding a single goal, with 10 goal difference by Sudden Death, 10 times, without dash, with five counter attacks, without kick and without jump.