suppermariobroth:

In World 4-Castle of New Super Mario Bros. Wii, it is possible to create an infinite amount of coins. If a fence-climbing Koopa Troopa is frozen by a character with an Ice Flower or Penguin Suit, then the rotating fence activated before the frozen Koopa touches the ground, the block of ice will enter a glitchy state where it will spawn several coins every frame. If these coins are not collected quickly, the game will freeze due to being unable to display that many objects at once.
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