The Whalers wear industrial gas masks used in whale oil processing plants, presumably to protect themselves from the rat plague and conceal their identities. Their base of operations is the former Chamber of Commerce in the Flooded District.
Before being recruited by Daud, they were mercenaries, street kids and refugees. They appear at times to attack Corvo Attano and were involved in the assassination of the Empress, Jessamine Kaldwin. There are three different ranks of Whalers during the game: novice assassins wearing gray outfits, master assassins wearing dark blue outfits, and unique leader assassins such as Daud and Billie Lurk wearing dark red suits. All members make use of the same weapons and masks. [Source: wikia]
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