When using Signet of Agony (Aura effect for Bone Curse) all of the utility interactions get disabled.
This includes for certain the slow effect from Crippling Anguish, and the Mark for Death effect from Sigil of Mortality. Neither are affecting the enemies. Will update once leveled up a bit more to see if anything else is affected but assuming there will be more.
Assuming this is definitely not intentional since the slow effect is literally the preceding node in the skill tree.
Easy enough to reproduce, just need a character with points in each of these skills and walk up to a mob. Mob is not slowed and has no visible debuffs on it or Mark for Death icon.
I’ve noticed there are threads on this topic from while back but they are locked now so wanted to resurface this. Not sure if it was never fixed or if it was fixed and has now become an issue again.
UPDATE:
Also noticed it costs mana to deactivate the ability. So I am paying 21 mana to activate → 15 mana per second → 21 mana to deactivate.
There should not be a cost to deactivate.