I really like the look of Cortex Prime, but I have not been able to totally grok it yet.
I don't understand how combat works. Is it possible to run the combat like a more traditional system like DnD or Savage Worlds?
I have to disagree with
@aramis erak somewhat. Cortex feels very different from D&D to me. It is more theatrical. That isn't to say that it its tactical, but combat is more about putting together a dice pool based on attributes, skills, etc. So if a goblin (DM) attacks a fighter (PC), the DM would say select the die for fight + the die for physical + the die for cutlass, etc. Roll the dice and add them together. The player would similarly select a combination of attributes, skills, weapons, etc., roll the dice and add them together. If the players roll is higher he successfully avoids the hit. If he rolls lower, he could take a complication. Complications are stepped up until you are taken out. In Cortex the strategic fun in putting together your dice pool to increase the odd of rolling higher than your opponent.
Of course it is all just different ways of abstracting prowess, armor effectiveness, weapon deadliness, etc. The the feel is different. I find Cortex Prime naturally encourages more narration of the results because you are not just chipping away at hitpoints.
Cortex Prime is, however, a modular, build-your-own system. So while, for example, initiative is not a core rule, it is an available mod for building your system.
You don't have to build your own. There are a number of prebuilt systems using Cortex and if you are familiar with one you can quickly pick up another because the core engine is the same. Hammerheads is free sci-fi game built on the new Cortex Prime engine that you can look at for an example. If you buy the Cortex Prime book, it also includes TRACE 2.0 which tries to emulate a police procedural and Eidolon Alpha which is a "neo-classic" fantasy. These three games (Hammerheads, Eidolon Alpha, and TRACE 2.0) do a nice job highlighting the versatility of the Cortex Prime system.
One campaign idea I've been tinkering away on is a Cortex Prime built campaign where players are caught in a massive virtual reality system and they have to find the truth of reality and their way out of the system by exploring through various settings, fantasy, old west, sci fi, etc. Different mods would apply in different systems so that while the core of their characters remain the same, the rules of the world may change as they move from one environment to another. Certain aspects of their characters will also change while a other aspects stay part of their core being. This is a much easier to emulate and run using Cortex Prime than in any other system I've looked at.