This game measures everything in inches, and it measures constantly. Every move, every reach check, every question about whether a model is near enough for the fight to happen at all. A dedicated widget answers those in one motion instead of two.What you get is a single piece of transparent green perspex, laser etched, cut to give measurements at four inches, three, two and one. The transparency is the practical part: you can set it down over terrain and models and still see what is underneath, which a steel tape will not let you do.Here is why it earns its place in this game specifically. Moonstone is decided by card duels, and a card duel only happens once a model is in range. Arguments over a sixteenth of an inch are how a friendly game turns sour, and a fixed widget removes the argument: the distance is either covered or it is not. It is also faster, which counts for something when both players are already spending their attention on what the other one might be holding.A small purchase that quietly improves every game after it. Most people who own one end up wanting a second so their opponent stops borrowing it.