Assured and unassured roll

The rules often use a mechanism for making a roll easier or harder called assurance (unassurance).

On an assured roll, you have one extra die. Of the three dice, you choose the two better ones.

More assurances mean more dice and thus a higher chance of success.

On an unassured roll it is exactly the opposite: you have three dice and take the worse ones.

Assurance and unassurance cancel each other out.