Cortex Plus

The Cortex Plus system was created by Margaret Weis Productions to support a wide range of RPGs. That company largely makes RPGs based on existing franchises, such as Firefly (where I learned of it from). Because the system itself needed to support not only Firefly, but also wildly different franchises, the Cortex Plus core was designed to be as flexible as possible.

This article is going to explain the absolute core of Cortex Plus like the d20 system did for 5E/Pathfinder. It won’t go into many details, much like that article didn’t. Later articles will compare how 5E, Pathfinder, and Cortex Plus solve similar problems and that is where we will go over mechanics in detail.

Cortex Plus is a more complex system than d20, yet ultimately solves the same problem in a very similar manner.

Like d20, Cortex Plus has a target number that you need to perform an action. We’ll just go ahead and call it a difficulty class, because the concepts are exactly identical.

Unlike d20, we aren’t rolling just a single d20. In fact, we’re never rolling a d20 because the dice in Cortex Plus ranges from a d4 (a four-sided die) to a d12 (a twelve-sided die). In order to attempt to meet the difficulty class, you roll some number of different-sized dice and get to keep the highest two. You are virtually always rolling at least two dice and if you’re playing to your strengths you’re often rolling not only larger dice (d10 or d12 instead of a d4), but also more than just two dice.

Of note, you also have no static bonuses to anything, ever. If I roll a d4 and a d8 and get a 2 and a 4, my answer is 6. Period. If I want to get a random bonus, it doesn’t come in the form of a +2, it comes in the form of another die.

So what advantages does this system have?

You get to roll a lot more dice! As silly as that sounds, it actually can be a positive. Rolling dice is fun and you feel powerful rolling a handfull of dice.

It actually leads to some interesting optimization decisions. Is it better to try to get your d6 that you roll all the time up to a d8, or to add another d6 to the roll? What if you could add a d8 to the roll, but only 50% of the time? Is it better to upgrade the d6 you always roll to a d8? These are question that you can do actual math to answer (to some degree), but they aren’t trivial to answer in your head and are more interesting than the decision to increase the modifier for your most-used skill that is common in d20 systems.

There’s some very easy things you can do for your players that doesn’t actually impact their power all that much. Giving them an extra die on a roll feels nice for them. Statistically it doesn’t help all that much.

The numbers are smaller. Since you only get to keep two dice (usually) and they only go to d12s, the absolute most you can get barring getting to keep an extra die for some reason is 24. As you power up your average number goes up, but your maximum does not. This makes balance quite a bit easier versus, for instance, higher level Pathfinder play.

Downsides?

Despite the fact that I like this system, I can’t deny that there’s plenty of negatives.

More dice are involved. That was a positive, but it’s also a negative. It can slow the game down. You can find the highest two then add those a lot faster than you could have added *all* the numbers, but it’s still slower than rolling a single d20 and adding a static number assuming you know the number and don’t have to look it up.

The optimal flow for rolling dice is a bit slower. This is pretty nitpicky, but I found that when I roll physical dice in Pathfinder I land in a pattern. I roll the d20 *while* I am looking for what my modifier is. I find that it’s +6, then look at the die, do some math, and give my answer. It’s smooth and quick and it is possible because I know that I start with a d20. In Cortex Plus I cannot do this because I have to look at my character sheet for two or more dice sizes before I can even roll.

The numbers are smaller. Yup, this is also a positive and a negative. There’s something awesome about saying “I deal 400 damage to the bad guy.” You’re never going to do that with a Cortex Plus game.

Would I use this system? Sortof. There are parts that I really like about this. I like that my skills are represented by dice sizes instead of numbers. I like the inherent cap on how big things can get by never going over a certain die size.

Most of this part of Cortex Plus I’m honestly not in love with. I think that at the core level that we’re currently looking at, d20 is the better system. When we get into the more in depth articles, something that you’ll notice though is that this whole system enables some things that I love to a ridiculous amount. Ideally I will find a way to keep those things, and that might necessitate keeping this part, too. We’ll see.