This passive is the core of my gameplay build, and I love the way it functions. However it's biggest flaw is that you cannot see what buffs you have on you when they are procced by this passive. For example, if I apply 10 Weakness to myself, I see the 10 Weakness disappear from my debuffs, but I don't see a buff with the Corresponding +20% damage dealt for 7s buff from consuming the Weakness.

Another issue is that there's no clarity on how strong the Debuff you're applying to yourself is, is it based on your Ailment Efficiency, if that's the case then at 9 stacks of weakness, I'm at -13% damage dealt (based on my stats), with a +20% damage boost from the buff. That's only a 7% increase in damage until I reach 10 stacks of Weakness and reconsume them for the buff, as I get closer to reapplying the buff, the less damage I deal. That doesn't feel very good.

Same issue applies to Stasis and Curse. Where they each reach a 7% increase in Movement Speed and a 17% increase in All-Resist respectively.

My suggestion is to have the buff applied by the Fatal Pact passive prevent you from gaining ailments during the duration of the buff. This would prevent you from having negative effects during the buffs, but also force you to reapply all 10 stacks every time it ends, rather than having a constant flow of increase and decrease in damage. If this would cause a balance issue or make the passive too OP, then that's understandable. At the very least can we have a UI indicator that shows the duration left on the buffs I have applied (A better ailment UI would be nice as well, currently they are too hard to see and sometimes overlap the area near the Revive Tokens or each other. I had Weakness on top of Burning on top of Poison in one "slot" of the Ailment UI for example.)