Dr. Arthur Conan Doyle

Combat Alchemy: By expending a use of Alchemic Concoction, Dr. Doyle can grant either 1d4 or 2d4 to a roll. Choose the roll to augment, then roll 2d4. If both the numbers
are either both even or odd, your augmented stat gets the rolled bonus. If each are different (one number is even, one number is odd), take the higher number to your augmented stat.