Challenge

Challenges are Agents' tasks. Nearly everything that Agents do, from recruiting mercenaries to dethroning monarchs, is a Challenge. They are the evil counterpart to Quests. Boiling actions down to specific Challenge types and difficulty levels plays a prime part in making the game manageable.

Challenge Mechanics
There are seven types of Challenges, each of which corresponds to one of the Agent's stats - a higher stat means that the Challenge completes faster and that higher-difficulty Challenges can be attempted. Infiltration Challenges set up spying, Ritual Challenges perform arcane workings, Terrorize Challenges induce panic and fear in the populace, Recruit and Muster Challenges deal with minions and armies and use Command as a stat, and finally Excavate and Construct Challenges have Labor as the defining stat. Defense is the only stat with no corresponding Challenges.

A Challenge is also assigned to Tier I, II or III. Currently the Tier I Challenges are the most difficult and Tier III Challenges the easiest, but there is discussion to change this order both to conform with the conventions used in other games and to allow for more flexible mod-ability. At any rate, the Tier influences two things:
 * Completion time: Challenges take time, during which your Agent can be discovered by meddling Heroes and potentially interrupted or even faced with combat. Higher-tier Challenges take more time than lower-tier Challenges. The Agent's relevant stat also affects the time taken. An Agent never fails a challenge due to random chance, so even a low level Agent can complete a Tier I challenge.
 * Opposition and Profile: Low-tier Challenges are hard to notice, and the AI is unlikely to commit serious opposition to your Challenge even if it does notice it, unless you've already done a bunch of things it didn't care for. High-tier Challenges draw more attention, the POI itself resists more fiercely (it uses a bigger fraction or even all of its Order value against you), and nations will send Heroes and/or Champions to your location to stop you.

Each time you complete a Challenge, successfully or not, your Agent incurs Fame based on a number of factors, but primarily based on the Challenge's Tier and the effects it had on the world. The bigger the bang, the bigger your Fame. High Fame reveals an Agent's location to the AI and quickens its response to future Challenges the AI may attempt.

Certain post-Challenge options may allow you to lower the Fame your Agent incurs for a Challenge, or even raise it further in exchange for some enhanced effect or additional benefit.

Can an Agent abandon a Challenge early?
Yes, if circumstances so dictate, you can abandon a Challenge (presumably to get your Agent to safety and/or to react to something even more interesting happening nearby). Depending on what you were doing and how far along you were, you may still leave clues behind and/or incur Fame for the partially-completed Challenge.