Monday, June 17, 2013

How Criticals Work

Hey everyone!

Today, we thought we’d let you all have a look into the mechanics of Vigilante. When playing an RPG, criticals, both failure and success, are the most exciting rolls. They change the pace of the game, make for moments of awesome, or lead to great tragedy within the game. They make the roll exceptional.

So, today, we are looking at the mechanics of critical successes and failures with the Vigilante system. In the Vigilante system, what specific dice you are rolling is determined by a difficulty set by the Director, which will be discussed in further depth in a future blog post. Success and failure all depends on how you roll and what are the skill numbers you are comparing them to. Skill numbers are set by one or a combination of stats on your character sheet. In Vigilante, when to trying to succeed at any roll, you are trying to roll at or below your skill number for that specific task, like how in Blackjack you are trying to roll 21 or under. In Blackjack, if you go over 21, you fail. If you stay under or at 21, you succeed, with the closer to 21 being better. If you stay under your skill number you succeed, while if you go over that number, you fail.

How does this translate to critical success and failures? First, whenever you roll doubles, that makes the roll critical, whether it be a success or a failure. Also, rolling on your skill number can make a success critical. In a contested roll, a critical failure always loses and a critical success always wins, in contest with a normal roll. Getting a critical success adds +5 to your roll.

What do you all think of these critical success and failure systems? Tell us in the comments.



  1. I'm not a fan of critical failures (in fact, we recently ditched them from the rewrite of our core mechanics) - primarily as for the most part, they're nothing more than a random chance that a player character is punished and as a designer and GM, I'd rather punish a character for their own stupidity than let the dice have a (usually) flat, statistical probability of doing it for me. This becoms less of an issue if the game mechanics do something to reduce or otherwise mitigate critical failure as a character grows in experience.

    Which brings me to my next point. Does Vigilante use a dice pool mechanic or is it a more traditional attribute + skill type affair? If you're using a pool and that pool grows with character experience/progression then the probability of rolling a double increases with a larger pool (assuming if for example, you had a pool of 4d you're just looking at matching any two results to get a critical). This is great for critical successes but suffers the same problem as oWoD used to: more experienced characters have a higher probability of critically failing. This is (IMO) a bad thing.

    There are a number of interesting threads on the RPGNet game design forums at the moment discussing mathematics, probability and randomness in RPGs - worth the read.

    1. Hi Andy, thanks for commenting!

      I'm going to go ahead and jump in here to answer this. The issue with criticals in most systems (such as d20) is that you have a flat percent chance of a roll critical failing, regardless of the relative skill of the character. In Vigilante, that's not the case.

      The way the dice work (and we'll be doing a full blog post about this soon) is that the size of the dice you roll varies with difficulty, while the target number is determined by your skill. It's a bit of an inversion of the traditional model. So if my skill at fixing my car engine is 9, I have to roll 9 or under to succeed. If it's an easy repair job, I'll be rolling 2d4 or 2d6. If it's a more difficult repair job, I'll be rolling on perhaps 2d10.

      That said, rolling higher is always better. It's like a blackjack system. Higher is better, until you cross over your threshold--in this case your character's relevant Skill Number.

      It's not a dice pool; it's almost always two paired dice (except at really high difficulty levels, but that's another story).

      So the way this affects criticals is that, well, any double is a critical--whether it's a success or failure depends on whether that roll would have otherwise been a success or failure. So your chances of success and failure remain the same, there's just a chance that either result will be more extreme. If you actually are so skilled that it's impossible to fail, then it becomes impossible to suffer a critical failure as well; at that point, any critical would be a critical success.

      Hope that answers your questions! I'll go check out RPGNet. Any particular threads you'd like to point us toward?