A fellow crafting enthusiast and I were discussing the disappointment of getting an Excellent when you're on the last step of a difficult synth.

We came up with this:

Hail Mary Byregot
Increases quality. Efficiency: 250%
Success Rate: 50%
Durability loss of 5
Can only be used with 10 or less durability remaining and material status of Excellent

(Alternate ability names: #YOLO, Byregot's Dice Roll, Nothing to Lose)