Cloaks are used to protect the living from losing their souls in the Netherworld. Anyone traveling there without a cloak, would eventually turn into a folk.
Ellen is given the Cloak of Sidhe in the Prologue, which later can be transformed into six other cloaks, each with their own special properties.
The downloadable content can add different appearances for the cloaks but does not alter their properties. The appearance can be changed at the 'Load Game' screen from the Costumes menu.

List of Cloaks

Navigate Costumes & Cloaks

• Ellen:   NormalCloak of Sidhe Faery Cloak
Battlefield Cloak Cloak of the Deep Cloak of Dawn Cloak of Twilight Cloak of Midnight Sun
• Keats:   Normal Transcended

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Life DropsMemory StonesCloaksPicture BooksKarma Release ItemsEvent Items