An excellent success die is a die that results in a value of 10 (the opposite of a botch). Excellent dice do not add extra successes, rather they add the chance of more successes, in other words they add more dice to the roll. For example: Consider you are rolling four dice at difficulty six, you get: 4, 10, 5, 8. There are two dice that returned a value of six or more, but one of them was an excellent die, so you get one more die to roll (one extra die per excellent die). Let us assume that extra die returned: 3, which is less than six - so not an extra success. The result is two successes.

If the extra die had returned a 10, then it may be re-rolled too.

The extra rolls from excellent dice are made before deducting botch die. If an extra roll results in a 1 (a botch) then it deducts a success, just like a normal botch die.