Pokémon Mystery Dungeon: Explorers of Time and Pokémon Mystery Dungeon: Explorers of Darkness are a matched pair of Pokémon games for the Nintendo DS.
New features include the addition of Generation IV Pokémon, improved Wi-Fi features, and more touch-screen options than the predecessor, Blue Rescue Team. 491 of the 493 Pokémon are featured, as Shaymin and Arceus were not officially released at the time of the game's launch.
A 21-minute TV special based on the game starring Kurumi Mamiya aired in Japan on September 9, 2007 as a content of the program relating Pokémon, "Pokémon Sunday" produced by TV Tokyo Corporation. It was later dubbed in English in 2008.
The story begins with the player having been washed ashore by a storm. Meanwhile, the partner is nervous about joining the Wigglytuff Guild, a local exploration club, and gives up early. Walking along the beach, the partner encounters the player, and informs that the player has been turned into a Pokémon. After a brief exchange, the partner explains their motivation for joining the guild; the partner loves legends and lore, and his/her life's dream is to find out what his personal treasure, the Relic Fragment, belongs to. Before the partner explains further, the Relic Fragment is stolen by Zubat and Koffing, members of Team Skull, which the player helps recover. The partner, reinvigorated by the player's courage, joins the Guild as a new team with the player.
The basic gameplay is unchanged from Blue Rescue Team and Red Rescue Team - players may use Treasure Town to link moves, save money, buy items, and store items, or to train in a special "maze" level (although the Pokémon running them have changed). Players will enter dungeons to complete missions, and during exploration they will encounter hostile Pokémon. During the story portion, if either the player or their partner is defeated by running out of health, the team will be removed from the dungeon, but lose all money and half of their items.
New to this series is the option to temporarily send a team member to aid a friend who is in need - this allows a team to have more than four members. Defeated teams awaiting rescue may also engage in a "standby adventure" mode in which players may revisit previous dungeons to raise funds and collect items, but without the ability to level up.
Among new items introduced are treasure boxes, which require money to be opened and may contain rare items. Rare items, however, may only affect certain Pokémon. They can also be used to trade for rarer and more valuable items using a new shop. New items are also introduced to account for new evolution methods which do not translate well from the main series to Mystery Dungeon (such as Probopass, Magnezone, Leafeon, or Glaceon). Pokémon eggs have been introduced to Mystery Dungeon, where the newly-hatched Pokémon will join the player's team. Finally, "Friend Areas" from Blue Rescue Team and Red Rescue Team have been eliminated in favour of a more streamlined team management process.