The briefcase of disguises is a reward from Penguin Hide and Seek. It is automatically unlocked after spotting 60 spies. The briefcase is a transmogrification unlock that allows you to temporarily visually transform into the following penguins:
- Sleeping penguin
- Captain Marlin
- Flippers McGraw
It isn't obtainable in its item form, and is accessed through the Emotes interface (in particular, click on the little ring icon 'Toggle between transmog items and emotes' in the bottom right of the Emotes interface. Then search for and click on the briefcase icon 'Briefcase of disguises').
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