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Coral is a minor obstacle found in Super Mario Bros.. In World 2-2 and World 7-2, coral proves to be a minor obstacle that can not harm the player. Coral is pink and acts similar to unbreakable bricks. The player can stand on the coral, but the enemies can swim through it. Coral also appears in Super Mario Bros. 3 in a few levels, but serves the same purpose as it did in Super Mario Bros.. It appears after a long absence in Paper Mario: The Thousand-Year Door, where it is found in an underwater level and can be destroyed by Bowser's Fire Breath.
Coral appears in the Super Mario Bros. and Super Mario Bros. 3 styles in Super Mario Maker. Coral is created by placing ground blocks in a stack in the underwater theme.