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Puddles[page number needed] are stage obstacles in Luigi Circuit in Mario Kart: Super Circuit and Mario Kart DS, and in Neo Bowser City in Mario Kart 7 and Mario Kart Tour (specifically in the course's final curve before the Glide Ramp). Like oil slicks, they cause any racer that drives past them to spin out and (only in Mario Kart: Super Circuit and Mario Kart 7) lose several coins.
Despite Neo Bowser City returning as a retro course in Mario Kart 8 and Mario Kart 8 Deluxe, puddles do not return as obstacles. In Mario Kart Tour, puddles are the main impediments in Tokyo Tour's Larry Cup "Steer Clear of Obstacles" challenge.