The Cosmere Roleplaying Game uses an original system designed for a broad range of players, from roleplaying novices to avid TTRPG hobbyists. The system's core mechanic is simple: roll a 20-sided die, add a relevant skill, and try to beat a certain difficulty number. Familiar but upgraded mechanics with purpose-built innovations such as talent trees, skill-based magic, and the �plot die� make the system unique!
The Plot Die
In the Cosmere RPG, when a character attempts something risky or dramatic, the GM can tell them to "raise the stakes." That's when the player adds the plot die to their d20 roll. This is a special die that can add an Opportunity or Complication to the result of a skill test. The d20 can also generate an Opportunity (on a natural 20) or Complication (on a natural 1)!
While certain rules in the game allow you to spend Opportunity or Complication for specific results, their primary role in the game is to add texture and excitement to the narrative. If you're a young Radiant trying to flee a group of ruthless Skybreakers, an Opportunity could mean you come across a temporary hiding spot, while a Complication might introduce a local constable who joins the people chasing you.
Combat, Conversations, and Endeavors
Cosmere stories feature incredible battle scenes, but put as much emphasis on interpersonal drama, making discoveries, and clever problem-solving. The Cosmere RPG provides rules to support every scene type and to seamlessly transition between them.
During combat, storytelling is at its most "zoomed-in." The system's first twist is its dynamic initiative order: every round the Cosmere RPG offers players a choice between "fast turns" (taking two actions before NPCs can act) and "slow turns" (taking three actions). The list of actions in combat also includes some fresh options, like using Gain Advantage to outwit an enemy, and the ability to "graze" a foe even when you roll poorly.
Conversations and endeavors are just as important to Cosmere RPG stories, and are supported with unique mechanics. In conversations, successful tests can wear down a stubborn NPC, but your adversary can make counterarguments that deplete your focus. In endeavors, players have the chance to use their skills in creative ways to engage in a range of scene types, from exploration and pursuits to infiltration and discoveries.
Choose Your Path
In most d20-based RPGs, characters choose a specific class that defines their capabilities, and "multiclassing" tends to dramatically dilute a character's power. The Cosmere RPG is built from the ground up to support flexible, talent-based character advancement. In this system, it's an entirely viable choice for a character to alternate between levels in Scholar (Surgeon), Warrior (Soldier), Leader (Officer), and Windrunner! Specialization and diversification can both generate powerful characters, and give you meaningful choices to make whenever you level up.
Improvisational Magic
Radiant paths give characters access to Surgebinding skills and techniques. Each Surgebinding skill lists specific baseline effects, and talents can unlock advanced capabilities like Soulcasting living flesh or creating Elsegates. However, the rules encourage players to use their powers creatively - just like the protagonists of Cosmere novels. The game rules provide specific answers to questions like, "How much faster can my Edgedancer move with Abrasion?" But this system is also ready to handle improvisational actions like using Abrasion to survive being swallowed by a Chasmfiend. (Roll Abrasion and raise the stakes!)
Of course, every magic system in the Cosmere will be different. Like Surgebinding, Allomancy and Awakening rely heavily on skill tests. You can attempt anything within reason by describing your intentions, rolling the d20, spending Investiture, and resolving the effects. Feruchemy and AonDor, on the other hand, offer powerful but more narrowly defined effects that reward well-prepared characters. In a Worldhopper campaign, you might even design a magic system of your own!
