Emissary uses a system with 8 primary characteristics, broken up into groups of 3 physical, 3 mental and 2 social. Each characteristic ordinarily falls within a range of 1 to 5 for baseline humanoid characters, but can be increased beyond this with racial bonuses, augments, power armour, special abilities or character advancement.
Skills similarly fall within a range of 1 to 5 and are broken up into small groups with an associated characteristic. A rank of 5 would represent a mastery of that skill.
To perform a skill check, a player selects the appropriate skill and adds their ranks to their associated characteristic score and then adds this to the result of a 2d10 dice roll. For example, a character with Strength 3 and Climbing 4 would roll 2d10+7 when making a climbing check. An average difficulty task is passed successfully if the result is equal to or greater than 14. Any circumstance which would increase the difficulty raises this target by 2, while any circumstance in the character's favour reduces it by 2. A range of examples are provided for each skill, although with common circumstances which could modify the target.
Each section of the rulebook ends with extensive examples of play, written in the format of a short story with a narrative description of the action alongside a rules breakdown of the same.