The rules for Specter are designed to be easy to understand, modular in nature, and complex in implication. This is the reference of all specific situations and such in the game rules.

If you can create an effort of 11+, you have the option to trigger special rules. You have to pay a Push and roll a d10 under five plus the effort in excess of 10. So 11 effort is 6 or less, 12 is 7 or less, and 15 doesn't even need a roll (10 or less).