- Smallville 18
Cortex Plus is the game system used for the Smallville RPG by Margaret Weis Productions. It's a non-traditional system, using a character's priorities and relationships to add to die rolls rather than their skills and natural abilities. Traits are rated from d4 to d12, and the two highest die results in any roll are added and used as the total. Characters have five Stress traits, also rated d4 to d12, which increase during play. Character advancement is done using a pool of Growth dice rolled against the difficulty of increasing different types of traits at the end of a session.
The idea of the game is to emulate the interpersonal drama of TV shows like Smallville, and it's modular enough to work with nearly any setting, though the overall feel of a drama show will generally remain.