Frequently, a player character will be called upon to make an attribute check (commonly called a "check"). This can happen in a variety of circumstances - most commonly, the character has chosen to take an action whose rules specifically request a check; alternatively, a non-player character has chosen to take an action targeting a player character, and that action specifically requests a check. Less commonly, the narrator may alert the player that something has happened (perhaps a natural disaster, such as a cave-in) that would require the character to make an attribute check.
An attribute check is a roll of the dice that, combined with the character's attribute, will determine the outcome of the situation: is that character successful in the action they have undertaken? Have they successfully defended against an incoming attack, or dodged that falling tree limb?
Making an attribute check is simple: you will need two dice, the attribute die (a d10) and the opposition die (another d10). Don't forget that these dice need to be clearly distinguished from each other! To perform the check, take the following steps:
  1. Roll both dice.
  2. Add your attribute to the attribute die.
  3. Add your opponent's attribute to the opposition die.
  4. If the attribute total is >= the opposition total, you succeed; otherwise, you fail.
Attribute checks will be worded to identify what attributes are being used; for example, if a player must make a Steel vs Wits check, that player will use their steel attribute (add it to their attribute roll) and will use the other character's wits attribute (add it to their opposition roll). Some checks will provide an innate bonus to the opposition - add the bonus as written to the opposition roll (e.g., a Steel vs Wits +1 check will add 1 to the opposition roll).
Sometimes, checks are not opposed (they do not target or directly involve another character). In these cases, the check has an intrinsic difficulty that takes the place the attribute, such as Bravery vs Difficulty +1. In this case, the +1 is the attribute added to the opposition. Difficulty values can be any number, including negative (meaning the task is very easy)!

Players Always Roll

An important part to note about attribute checks - the players always roll, the narrator never rolls. This means that if a non-player character takes an action that requires a check targeting a player, the player makes a defensive roll by simply switching the order of the attributes. For example, if a non-player character would make a Bravery vs Steel check targeting a player, the player rolls a Steel vs Bravery check.
Should a non-player character take an action that requires a check that is not opposed, the narrator should simply determine the result. If the narrator feels truly compelled to let fate decide, they can, in these limited situations, make a roll for the non-player character.

Critical Rolls

When a player is making a non-defensive roll, they have a chance to have a critical success. A check is considered a critical success if 1) it is already a success (a failed check cannot be critical), and 2) the unmodified attribute die is a 10 (the die itself must have rolled a 10 prior to any attribute values being added, or any other effects modifying it).
If both of the above hold true, the check is a critical success. In this case, it counts as a success as normal - in addition, should the action being taken specify a critical effect, that additional effect is added to the normal effect (in all other cases, the critical effect is ignored). The narrator may also opt to add additional effects or bonuses at their discretion for critical successes.
Some effects and upgrades allow a character to improve their chance of a gaining a critical success - these improvements will reduce the target number the attribute die must roll; the most common is the critical upgrade available to player characters as one of their upgrade options (see Story Points for details).

When Not to Roll

If a rules item (such as an action) calls for a check, then the check must be made. Otherwise, checks should be required for any action a player takes that does not have a guarantee of success; should an action be effectively trivial (such as walking down a paved road, or holding a conversation with a friend), no check is required. Ultimately, which actions require a check and which do not is up to the narrator, whose final decision stands.

Checks Against Other Players

Occasionally, two player characters may be in competition with each other; perhaps a friendly arm wrestling match, or perhaps something more dangerous or extreme. In either case, the "Players Always Roll" rule is slightly modified. Neither player rolls an opposition die - instead, each player rolls their attribute die, modifies it as needed, and their results are compared. Whichever player's result is higher determines the outcome; ties can simply be rerolled.
Next: Encounters