I confess that this phrasing confuses me in the rules and published adventures. Is it Difficulty 4? Is it risking 4 points lost from Stability?Four point Stability test for everyone!
I end up re-formatting all published adventures using my own standard phrasing for tests and clues so I don't miss them while I'm Keeping. The latest adventures, where Stability tests are just the points risked inside a graphic element are worse for me, because it's more work re-formatting.
My face-to-face game is slightly pulp, so I tell my players "Make a Stability test, Difficulty 4, please." and because they never remember the rules, walk them through it.