What is the formula for succes? Some say it is natural ability, some say it is skill and practice, and yet others say it is sheer luck. In reality, all three may have something to do with it. When Guillaume tried to pick the complex locks of the Ferdanian Reichsbank Vault, he surely had an aptitude for such things. Because of his good dexterity. But he was also very skilled at the ignoble art of intrusion. And above all, he was especially lucky that day.

There will be many times in the course of an adventure in which you try to do things of which the outcome is uncertain. Often the results will be fairly obvious, because the task at hand is so easy that you can hardly fail. Other times it’s just impossible to do, like trying to cast a spell when you don’t know magick. But many times, it will be something in between.

In all these cases, the Game Master? may ask you to either make a Skill Check, or an Ability Check. You make a Skill Check when you have a particular skill that’s very suitable for the task at hand. If you do not have any applicable skill, or if it’s something very general you try to do (jump over a ditch, for example), you make an Ability Check.