Here are the basic rules for Espionage. Factions get an opportunity for espionage every two weeks.
Note that there are two questions for every mission:
- Success: Did they succeed in blowing up the building, stealing the secrets, or whatever their mission was?
- Evade Detection: Did the target faction catch them, or at least gather enough information to prove whodunnit?
These are independent questions, and evading detection is generally harder than succeeding in the first place. An agent can fail in their mission and be caught, or succeed in their mission but be caught (or leave enough evidence to prove they did it), or fail in their mission but evade detection (e.g. realizing it’s not going to work and sneaking off before trying it), or succeed in their mission before vanishing without a trace and returning home to have a martini.
If a faction is caught, a third question arises—how severe the consequences will be.
Calculating the Odds
Each faction has an Espionage trait (average 50). This sets their baseline chances for succeeding at a mission and evading detection afterwards.
These baseline odds are further modified by mission-specific difficulty levels:
- Trivial: +40%
- Easy: +20%
- Standard: Baseline
- Difficult: -20%
- Longshot: -40%
- Metal Gear: -75% (name courtesy of Naggarok)
For example, if Pinguland has an Espionage trait of 60, it has a 60% chance to succeed at a Standard task, and a 40% chance to succeed at a Difficult task. Results are rolled with a d100.
Critical Successes and Failures
On a natural roll of 80 or above, the faction automatically succeeds, in an especially exciting way. (Good material for lore updates.) On a natural roll of 10 or below, the faction automatically fails. (Yes, critical failures are more common than critical successes.)
Missions
Other than Counter-Espionage, which is purely defensive, each mission has the following traits:
- Mission Difficulty: How hard the mission is to pull off. (See “Calculating the Odds”, above.)
- Evasion Difficulty: How hard it is to avoid being caught, either during the operation or afterwards.
- Stigma: How awful the international community considers this kind of action. Measured in terms of how much Favor is lost. A faction that gets caught conducting espionage operations will lose the specified amount of Favor, then make a Sanctions check.
- Note: If a faction succeeds in its mission, but evades capture, it acquires a Secret of severity equal to its Stigma rating. (See the “Expose Secret” option for more information on how Secrets work.) If this Secret is exposed, the faction also suffers whatever special penalties it would have faced had it been caught red-handed.
The list of missions follows.
Counter-Espionage
- If the faction decides not to conduct an “offensive” mission, it focuses instead on checking for enemy agents.
- Mission Difficulty: Special.
- Evasion Difficulty: Special.
- Stigma: n/a
- Counter-Espionage gives a pretty decent defense. It’s usually worthwhile unless a faction really wants to conduct some other mission.
- Counter-Espionage provides two benefits.
- First, completely independent of what the enemy agent’s odds of success or evading capture are, the defending faction has a 20% chance to thwart the mission and a 30% chance of exposing the enemy faction’s involvement.
- Second, the defending faction gets to make two counter-espionage rolls at baseline difficulty: one to thwart the enemy mission, and one to expose the enemy agent. For each roll, if the defender’s margin of success is more than double the enemy’s margin of success, the enemy fails the roll. (Critical success and failure rules apply. If both sides score a crit, the side that rolled better wins; in case of a true tie, the defender wins.)
- Example: Pinguland has Espionage 50. Rengarville attempts to commit some act of espionage against Pinguland. First, before anything else happens, Pinguland has a 20% chance to thwart the mission (regardless of what Rengarville rolls) and a 30% chance to expose Rengarville’s deceitful acts (regardless of what Rengarville rolls). Let’s say Rengarville stealths past both of these. For this example, assume Rengarville has an 80% chance of success and a 50% chance to evade detection. It rolls a 50 to complete the mission (margin of success: 30) and a 40 to evade detection (margin of success: 10). Normally, this would mean that it carried out the mission and evaded detection. Not so fast, Rengar. Pinguland gets a no-modifiers Espionage roll for each of these. First, for the mission itself, it rolls a 30. That gives it a margin of success of 20, which is not more than double Rengarville’s margin of success (which was 30). So Rengarville succeeds in the mission. Next, for evading detection, say that Pinguland rolls 15. That gives it a margin of success of 35, which is more than double Rengarville’s margin of success for evading detection. Rengarville succeeds at stealing tech secrets or blowing something up or whatever else, but Pinguland finds proof that Rengarville was behind it.
Sabotage Research
- Disrupt the target faction’s research, setting them back and potentially triggering a disaster.
- Mission Difficulty: Standard (Espionage)
- If successful: target faction loses its next set of research rolls and must make a Danger Level check at double the usual Danger Level.
- Evasion Difficulty: Difficult (Espionage -20%)
- If the spy is caught, the target faction loses its next set of research rolls, but does not have to make a Danger Level check that week. The target faction will instead be spending the time checking and double-checking everything to make sure it’s safe to proceed.
- Stigma: 10 (increased to 20 if the target faction fails its doubled Danger Level check).
Steal Research
- Swipe some research from the target faction.
- Mission Difficulty: Difficult (Espionage -20%)
- If successful: next week, gain bonus research equal to three times the target faction’s base research score.
- Evasion Difficulty: Difficult (Espionage -20%)
- Stigma: 10
Pilfer Assets
- Swipe some valuable resources from the target faction.
- Mission Difficulty: Difficult (Espionage -20%)
- If successful: take 20% of the target faction’s current Commerce balance.
- Evasion Difficulty: Longshot (Espionage -40%)
- Stigma: 10
Seek Forbidden Lore
- Swipe something from the Institute’s dark archives, trespass on a restricted zone (such as the Floating Pyramids), or otherwise violate the League’s rules to pursue forbidden knowledge. This knowledge is often forbidden for a reason: very bad things can happen.
- Mission Difficulty: Longshot (-40%)
- If successful: Gain 5d100 (average 250) bonus Research next week. (For comparison, a faction with 50 Research gains about 100 points per week normally.)
- Evasion Difficulty: Longshot (-40%)
- Stigma: 15
- Research rate is also reduced by 20% for the rest of the arc.

The League has harshly sanctioned Noxus for using spooky costumes and an old projector to frighten poor Mrs. Jones away from her mansion. [Secret — Darius defrauding old widows (10)]
Expose Secret
- Some factions have Secrets. (They’re listed on the World Systems page.) A capital ‘S’ Secret is something that many have cause to suspect, but no one can yet prove, but which would be damaging to a faction’s reputation and standing if such evidence could be found. Espionage agents can try to find some.
- Mission Difficulty: Difficult (Espionage -20%)
- Roll this chance of success for each Secret. On a successful roll, the Secret is exposed. The effects vary based on what the Secret was.
- Evasion Difficulty: Standard (Espionage without a modifier)
- Note that there are many completely legitimate ways to expose Secrets.
- There is only one “evade detection” roll, no matter how many Secrets the faction has.
- Stigma: 5
Muckraking
- Everyone’s got something to hide. Investigate the target faction and create some Secrets. (Remember that a Secret is something that’s strongly suspected, but not yet proven. Muckraking digs up these rumors, creating Secrets that any faction can then try to expose with the Expose Secret mission.)
- Mission Difficulty: Standard (Espionage with no modifier)
- If successful: Add d3 Secrets, each of severity 3d10, to the target faction’s list.
- Evasion Difficulty: Difficult (Espionage -20%)
- Stigma: 5
Bombing
- Set off a huge bomb (or something similar) inside the target faction’s home territory. This is a psycho option, and requires at least 65% support.
- Mission Difficulty: Easy (Espionage +20%)
- If successful: Lots of people die. Target randomly loses 2 Champions for the next weekend of Featured Matches. (They’re either injured or busy helping survivors.) Target loses its Research and Industry rolls for the next two weeks. Target loses 3d20 Commerce.
- Evasion Difficulty: Longshot (Espionage -40%)
- Stigma: 35
- Being caught triggers a devastating array of sanctions. The faction will likely become a pariah.
- Pay double the lost Commerce back to the victim.
- For the next two weeks of Featured Matches, and the next Tournament if any, the victim gets two real bans against the bombing faction.
- Being caught triggers a devastating array of sanctions. The faction will likely become a pariah.
Assassinate VIP
- Assassinate an enemy NPC. (For various reasons, no, you can’t actually kill them, but you can take them out of action for a while.)
- Mission Difficulty: Easy (Espionage +20%)
- If successful: NPC is taken out of play for the next d4 weeks.
- Evasion Difficulty: Difficult (Espionage -20%)
- Stigma: 20
Assassinate Champion
- Assassinate an enemy Champion. (For various reasons, no, you can’t actually kill them, but you can take them out of action for a while.)
- Mission Difficulty: Standard (Espionage with no modifier)
- If successful: Champion is taken out of play for the next two weeks.
- Evasion Difficulty: Longshot (Espionage -40%)
- Stigma: 15
- If caught: the guilty faction’s opponents get a free Champion ban against them in every match for the next two weeks.
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Why are some chances – and others are +? Is that a typo or something more?
Those are modifiers to be base odds, which are set by each faction’s Espionage stat.