Ruthless

The gem as others have said lacks transparency. Please add an indicator to show when a ruthless blow is ready. This is already done well for fist of war support and I can tell when it is ready by looking at the skill icon. Adding a similar indicator for ruthless would reduce confusion with its interactions by clearly indicating when it is active and making it easy to test and experiment with.

Another gameplay reason for adding indicators is to allow exert builds or similar mechanics that empower attacks to more easily align a ruthless blow and reward the set up. As is you pretty much have to guess when ruthless blow will go off if you don't keep count of every single attack since you entered a zone.