There’s only two abilities (that I can think of rn) that mordo does not have 100% accuracy on, his SP1 Stun, and his Sp3 regen, so in theory, this is easily tested, just hold the heavy and see if he gets critical failures
So all depends on if Domino's ability is passive which I believe it is. As opposed to kingpins sp1
This is correct; since Mordo's immune to passive Ability Accuracy reduction, he would be immune to Domino's Probability Field and Unlucky passive effects. On the other hand, Mordo is not immune to the Ability Accuracy reduction from the Black ISO-8 debuff caused by Kingpin's SP1, since that Ability Accuracy reduction is caused by an active debuff, not a passive effect.
He could also still be damaged by Domino's Critical Failure signature ability, since it is activated by an ability failing to activate, not by her Ability Accuracy reduction. So something like Mordo failing to cause a Stun with his SP1 or a Regeneration with his SP3 could activate Critical Failure. Hope this all helped clear things up!
The change to his ability description was not listed in any patch notes. The only thing listed was a change for his ability not to proc against concussion and fatigue, not including other active abilities that can reduce ability accuracy
Comments
This is correct; since Mordo's immune to passive Ability Accuracy reduction, he would be immune to Domino's Probability Field and Unlucky passive effects. On the other hand, Mordo is not immune to the Ability Accuracy reduction from the Black ISO-8 debuff caused by Kingpin's SP1, since that Ability Accuracy reduction is caused by an active debuff, not a passive effect.
He could also still be damaged by Domino's Critical Failure signature ability, since it is activated by an ability failing to activate, not by her Ability Accuracy reduction. So something like Mordo failing to cause a Stun with his SP1 or a Regeneration with his SP3 could activate Critical Failure. Hope this all helped clear things up!