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Doppelganger is a first officer command used by Wendy and Dieter in Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey. It is Wendy's second command, the first being Mystery Box. It costs 5 CP to use. Once activated, the user will create one or two duplicates of themself to fight on their side during battle. These duplicates attack the same way as the original and are nearly identical in appearance, the only difference being that hearts float around Wendy's clones. The clones will not disappear until they are defeated or the battle they are used in ends. The command cannot be used until there are only seven ally units remaining.
If an enemy captain uses Lightning, clones created via Doppelganger will not be affected.