A tone that deals extra damage scaled off the total debuffs of the target?
Rauðr-, Blár-, and Gronn- Bolt or whatever.
Good idea, broken, or just plain bad?
Edit: Should it still slow special triggers?
The effect isn't THAT good considering that buffs on enemies only really happens when you're facing enemies in formation, and oftentimes (when attacking), they break out of formation or you want them to. It does seem interesting, though we already have an effect like that in the form of The Cleaner+, though it is physical.
OP was talking about damage scaling off of enemy debuffs, not buffs. Although the cleaner doesn't scale off of enemy debuffs, guunthra's blizzard does.
To answer OP's question, reverse bladetomes are neat and interesting, but require a lot more work than regular bladetomes for not as much offensive power.
It's pretty good if you have someone like S.Linde or S.Kagero using smoke dagger or double smokes. They take out one target; Gunnthra goes in to deal with the tanky one. It has the added benefit of being immune to Aversa because Aversa can only mess up your visible buffs; if you depend on debuffs to the enemy the worst Aversa can do is debuff you for 3 to all stats to compensate.
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