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Sentry Duty (Japanese: みはりばん Sentry Duty) is a job in Pokémon Mystery Dungeon: Explorers of Time, Darkness, and Sky, played as a mini-game. It can first be played a few days after the player and their partner rescue Azurill. Various times during the story of the game, Diglett is unable to perform his sentry role, so the player and their partner are given the job instead. The player will be notified about this when Chatot tells them what he wants them to do for the day. After graduating from the Guild, the player and their partner can do Sentry Duty as much as they want.
The player is shown the footprint of a Pokémon entering Wigglytuff's Guild and must identify the Pokémon from a choice of four within a time limit. When a short time passes, the picture of the four Pokémon is displayed. When the time remaining drops to half, a short description of the Pokémon to which the footprint belongs is displayed. A second description is given when time is about to end. More points are awarded for quick identifications, while the player's partner will allow them to guess again twice if an incorrect answer is given. If an incorrect answer is given after this, Loudred will tell them what it is and then yell at them. After six footprints have been shown, and/or identified, Loudred calls out to the player and their score is evaluated. Chatot then rewards the player with money and various items depending on their score. However, if the score is very bad, Chatot tells the player and their partner off and gives them no supper, causing Loudred to be very mad at the player. This, however, does not lower the player or partner's hunger level, as it does not exist outside of dungeons.
The player gets bad grade for scoring 4000 points or less, adequate for 4001-7000, good for 7001 or more and a perfect grade for identifying all six footprints regardless of how many points they have scored.
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