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Core Rules

Core Mechanics

The Dice

To play OSR+, all you need is a six-sided die (d6). Ideally, two or more six sided dice (2d6) for the optimal experience. All of the tables in the system are designed with a range of 1 to 6, and all of the rolls entail rolling one or two d6s at most.

It's a good idea to have a full set of polyhedral dice on hand, however, and you can get a set for less than twenty dollars at your local hobby store or online. This will help with any arbitrary rolls the GM might call for at the table.

The Conversation

When you do things in the game, the order in which you declare them matters. There's a cadence to the conversation, and it goes like this:

  1. You say what you want to do and how you do it. 
  2. The GM figures out if there's a roll involved or not, and if there is, you roll. 
  3. Then the GM says what happens. Rinse, repeat.

Before You Roll

You declare what skills you’re using, and whether you plan to use a story tag. You can’t add a skill or story tag after you roll.

Before the GM resolves your action

You declare any spells or abilities that might alter a roll (unless the spell or ability says otherwise).

After You Roll

The GM uses the core mechanics or may make a ruling in the spirit of the core mechanics to decide your fate.

Rules vs. Rulings

A ruling is the creation of a new rule to resolve action in the game in a way that is not explicitly laid out by the rules-as-written. The GM may make rulings whenever necessary, so long as the ruling doesn't contradict the rules-as-written. (See notes on the fiction for exceptions to this rule.) When making a ruling, the GM's first priority is to be fair, and his second priority is to rule in a way he thinks makes logical sense, given the circumstances of the fiction at the moment of the ruling.

Impossible Rolls

Sometimes it may seem impossible to fail, or impossible to succeed. For example, you need a target number (TN) of 7, but you have an attribute of 6 and a skill that adds +2—it would seem you can't roll below 8. Because of exploding dice and critical failure, it's always possible to succeed or fail. Always roll, even if the numbers say you can't fail.

Critical Success & Exploding Dice

Any time you roll a natural 6 on a d6, the die "explodes": you must roll again and add the result of the second die to your roll. If you succeed on the result, this is considered a critical success. Keep doing this as long as you roll natural 6s.

"Natural" means the die landed on that result and was not modified by other mechanics to equal that result.

Critical Failure

If you roll a 1 on a d6, there is a chance of critical failure. (We sometimes refer to this as “confirming a critical.”) Immediately roll 2d6 to confirm the critical; if you roll snake eyes (both dice turn up 1s), then you have critically failed. Don't bother tallying up your original roll, because even if you would have succeeded, you do not. The GM will decide what mishap occurs that magnifies your failure.

Critical Failure on Exploding Dice

If you roll a 6 (which explodes, so you roll again), and then you roll a 1 on your exploded die, you still need to confirm the critical. If you critically fail on the exploded die, it means you’ve pushed your luck too far: stop rolling and follow the rules for critical failure.

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