During P2 of Sith raid, Sion inflicts Pain on other characters. This works fine and with the raid dynamic, it locks the debuff in place only to be removed by soothe. If you use General Kenobi's second ability, "The Negotiator," it will remove all debuffs (except pain, obviously), and give retribution to all characters without debuffs. That being said, if a character did not have a debuff, but did have pain, it will not grant that character retribution.
Since "The Negotiator" is not supposed to trump "Pain," and I agree it shouldn't because that's the raid dynamic, I propose that it not be counted as a debuff for this ability. I don't know of any other cleansing abilities that this would affect like this one, or I would've listed them here.
This is also true in P4 as well.
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