Alter Aeon Online Help

Keywords are:  'thief skill shadow cloak of darkness'

Skill: cloak of darkness        Move:   1  Shadow Cost:   9  Lvl 13 Thie  (28%)
                                (critical)   
                                Group: Thief shadow disciplines

Usage:
shadow cloak [off]
cloak darkness [off]

Cloak of darkness allows the thief to gather shadows around himself, covering
light sources and improving his ability to hide. The shroud of darkness
persists for as long as the thief can maintain it.