I see that potencial Domino's passive ability makes her so unfair to fight. It should be adjust from 3% to 7%.

15% means that ONE action of yours can fail every 6 or 7:
- you do 2 combos with 3 and 4 hits, and instead of get a critical hit, it will fail;
- any mastery can fail in every 6 or 7, like dexterity, parry, block prof., assasins, etc;
- the regen ability with 15% can fail when triggered;
- abilities like stun in specials, from 100% to 85%, every 6 or 7 can fail;
All this together, Critical Failure can trigger every 6 or 7 actions you do but don't, thanks to that 15% ability redduction. if this value were changed to 3%, that number 6 between 7 would be 33, 33. Or if it was changed 7%, the number would be 14,28.
Think about it, even it was 7%, every 14 actions is a decent number compared to the actual 6 or 7. Or 3% is like some passive evades, is a smaller number, but it still work, sometimes a lot in a single fight.
Like others champions, GP, Scarllet Witch, Thor, Wolverine, Red Huk, Luke Cage, with his skills adjusted to maintain the balance between the other champions and his abilities, this could really be something valid. (this is just an example Kabam has already argued).
Plus if any of her abilities fails to trigger she gains 10%, that means in the beggining of the fight you already with 85% ability accuracy (Kabam says any champion has 100% as base), when any of her ability fail to trigger she gains 10% (ex.: she can't bleed with SP1, then for 8 seconds she gains 10% ability accuracy).