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Yarn Blocks are a special kind of block seen in Wario Land 3. They are commonly featured in levels that require Wario to transform into Ball o' String Wario and serve as obstacles, blocking Wario from accessing certain areas. These solid blocks cannot be destroyed by normal means. To break through them, the players must approach them as Ball o' String Wario, The impact will then break the blocks, clearing the path for Wario to progress further. They act in a similar way to Snowman Blocks, seen throughout other games in the Wario Land series.