Hacking Cortex Plus for Star Trek

Hacking Marvel Cortex (the Marvel Heroic RPG by Margaret Weis Productions) for use in a Star Trek campaign turned out to be pretty easy. The core mechanic of Marvel Cortex is the dice pool, where dice are derived from different sources such as Powers, Expertise (Skill), Affiliation and so forth. The question was how to make the dice sources appropriate for a Trek campaign?


I kept Distinctions as is. These make great descriptors and role-paying hooks - Klingon Wannabe, HotShot Helmsman, A Girl On Every World, all great ways to help define characters, giving them niches and possible complications.

I replaced Affiliation with Rank. Ensign and down d4, Lieutenant (including JG) d6, Commander (including lieutenant) d8 and so on.

Expertise remained the realm of skills. I included a catch-all Starfleet Training d6 to reflect the broad training characters seem to have in Star Trek. Then I set 3 levels d8 Specialist, d10 Expert and d12 Master. Like in Marvel, the expertise areas were somewhat broad, including Marksman, Hand-to-Hand, Tactical (ship combat), Helm, Engineering, Covert and so on.

I replaced Powers with Traits. These included Exceptional Attributes such as Strength or Intellect at d10, special abilities such as Leadership or Born To Fly, and 1 limitation for each character.

Finally, I have Equipment. It could be a Tricorder d8, a Phaser d8 or other appropriate gear.

Once the characters were put together, I tinkered with the Doom Pool, changing the name to the Complication Pool. Ones on the GM dice remained Opportunities. Instead of using pushes and stunts, players paid 1 plot point to add the Opportunity Die to their pool for their next action or reaction. Whenever a player rolled a 1, I paid them a plot point and added that die to the Complication Pool.

Instead of rolling the whole pool, the GM dice are referred to as the Opposition Dice. There are 2 static dice, 2d6, and the GM can spend dice from the Complication Pool to add to these. If the players are up against active opponents, their foes' appropriate dice are added, such as Klingon Warrior d10 or Hungry Targ d8. If they are up against a named opponent, that foe will have a dice pool in the same manner as the players, which is used in lieu of the static dice (but Complication Dice can still be added in).

I also ran a quick-and-dirty ship battle, assigning dice values to ship gear such as weapons and shields, and giving ships Shield, System and Hull Stress and Trauma.

A big part of the action was players creating Advantages to set themselves and each other up. Covering Fire, Taking Cover and On Their Six (in the ship fight) were examples of advantages they would set up. Overall it worked well, well enough that I'll have to come up with an advancement system. As much as I think Milestones are clever, they are a pain in the butt to come up with and use. Plus I'm not a big fan of players having their characters do something just for the xp as opposed to it being in character or missing out on xp because they decided to help their crew rather than follow an xp agenda.