
click to enlarge
If you can level your Crafting Tier’s Proficiency without putting all the extra resources into earning Mastery, why bother with Mastery? Well, it opens up Critical Successes. Once you have completed Proficiency and Mastery of a Tier, indicated by a bronze and a gold anvil beside the Tier Heading, selecting a recipe from that Tier will offer Mastery Options.
There are two tabs at the bottom of the Crafting Window. One shows the recipe and required components. The other, Mastery Options, is greyed out until you Master the tier. Clicking on it once it is available will show you what your Critical chance is, based on bonuses from tools and scrolls. It also shows what you will produce if you succeed. If you fail, you will produce the normal item from that recipe.
Most interestingly, it shows an item you can use to increase your Critical chance dramatically. If you have the item, you can click the check box to use it. It will be consumed whether you succeed or just generate the normal item.
Critical Crafting Successes either generate more of the normal item you are crafting, or a significantly uprgraded version of the normal version. In fact, Critical Crafting Success items are some of the best in the game for their levels.