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Question about the skill Dark Cloak for nightblade
It specifically states damage over time effects, as in DoT. So that would not remove any other "Debuff", otherwise it would have stated it along the lines of "Removes 1 detrimental effect".
EDIT: Sorry OP, forgot to answer your question.
What they mean by that, if a enemy hits you with an ability that makes your character take damage for like 10 seconds, using dark cloak will remove the 10 second damage from you.