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Munna is the leader of a gang in Pokémon Mystery Dungeon: Gates to Infinity that works for Kyurem to help eliminate any humans that come to the Pokémon world to stop the Bittercold.
History
At the beginning of the game, Munna is seen in a dream of the player as being chased by a Hydreigon and it is at first perceived by the player that the Munna is calling out for help. Munna later appears in the Forest of Shadows dungeon to set up a ruse to stop the player and partner Pokémon. It pretends to be scared and hurt behind a rock. Shortly afterwards, a Chandelure appears to light up the room and a bunch of enemies appear to surround Munna and the two Pokémon. The player Pokémon escapes, having realized that they left their partner behind, they realize that they have to press onward to the next dungeon by themselves. Munna and one of its henchmen Toxicroak are seen on top of Holehills discussing about the partner Pokémon, who is shown to be trapped inside a cage. Munna leaves, leaving Toxicroak behind to supervise the cage. Suddenly, Toxicroak is attacked from out of nowhere. The player then appears and checks on the partner Pokémon in the cage only to realize there is now a crystal inside instead and is ambushed by Munna and its gang. Hydreigon appears and fires several Dragon Pulses. One of the shots accidentally fires onto the cage and leaves nothing but a big gaping hole. The player goes to check on their partner and Munna gets itself together from the attack and orders Salamence to chase after Hydreigon and the two fly off into the distance. The player finds their partner alive at the bottom of the hole realizing that there is a set of stairs that lead downward. They hastily escape but are ambushed once again by Munna and its gang. Hydreigon appears and grabs the player and partner and flies away, but not without being injured by Salamence who lunges at them. Later at the Glacier Palace, Munna is shown speaking to Kyurem via telepathy and is soon interrupted by Toxicroak, who tells it that Salamence and Chandelure were defeated by the player and partner. It appears along with its cohorts in one last attempt to defeat the player, partner, and their team members. After defeating them, the floor above starts to cave in and collapses, it and the player and partner Pokémon are separated by a big chasm from the rest of their respective teams. Munna is severely injured and is unable to continue, the player and partner head into the next dungeon while Munna's minions express their concern.
Related articles
For more information on this Pokémon's species, see Munna.