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Stop Watches (also known as Time Stops) are clock-like items that usually slow down or stop time when collected.
Super Mario Bros. 2
If Mario or his friends first pulls up four large vegetables in Super Mario Bros. 2, pulling up what would normally result in a plant will instead reveal a Stop Watch. It will appear for a second and then freeze everything in the level for a few seconds. This gives a window of opportunity for Mario and his friends to defeat enemies and collect small hearts. However, touching the frozen enemies still hurts the player, but they will stay in one position and not move at all.
Paper Mario series
The Stop Watch later appears as an item in Paper Mario. When Mario or his partners use it, it will immobilize enemies for a few turns (assuming it is successful). It can be bought at most stores and is a fairly common item.
Paper Mario: The Thousand-Year Door
It appears in Paper Mario: The Thousand-Year Door under the name Stopwatch. Here, it is a somewhat rare item, for it can only be purchased in Twilight Town or Fahr Outpost. The item will immobilize enemies, just as in the game's predecessor. However, enemies can also use the item against Mario or his partners. Several warped clocks appearing in various colors will appear on-screen after using the item. After about four seconds, the item takes effect and immobilizes its prey.
Super Paper Mario
Donkey Kong Land III
A related item appears in Donkey Kong Land III. Stop Watches in this game, however, cannot be used during gameplay. They act primarily as collectibles which count toward a final game score of 100%, but also act to unlock various time trial challenges after King K. Rool is defeated for the second and final time. These time trials are merely select levels from the game which are timed, unlike in regular gameplay. Finishing six of the twelve total challenges, on top of collecting all major items in the regular levels, will lead to a perfect game score.
Nintendo Comics System
In the Nintendo Comics System story Cloud Nine, it appears as an animate object who acts as the Mushroom King's alarm clock, dodging the grumpy King's attempts to swat him and fearfully running to Princess Toadstool for safety.
Mario & Luigi: Dream Team
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