Running State Safely
This chapter is the one that keeps the system honest. Read it before you add any mechanic that remembers something.
The problem
Lancer is a game of consumables. Heat, HP, structure, stress, repairs, limited charges, core power, reserves, licence level. Every one of them changes during play and every one of them drifts if the GM is allowed to record the change in prose instead of in a field.
Drift is not dramatic. It is a sheet that quietly stopped being true in session two and nobody noticed until session nine.
The four pieces
Any mechanic that persists needs all four, or it is documentation rather than a rule:
- A rule in a GM instruction saying when and how it operates.
- A schema field that can hold it.
- A file holding the current value.
- A trigger or visibility setting that puts the rule in front of the GM at the moment it applies.
Three out of four does not work. The most common failure is having the field and the rule but no trigger — the GM never looks at the right moment.
The encounter contract
This system's answer to combat state is deliberate and you should not weaken it.
During a fight, the encounter file's combatants array is the only live record — for players and enemies alike. HP, heat, structure, stress, conditions, zone, stance and reaction use are read and written there, every turn.
Player mech sheets are not touched mid-fight.
When the encounter resolves, the GM copies each player mech's final state back to its own file, sets state to resolved, and sets syncedToSheets to true.
Two triggered GM instructions enforce this, and the encounter sheet shows a warning banner whenever a resolved encounter has not been synced. That banner is doing real work — it is the only thing standing between the campaign and silent drift.
Why not write to both
Because the mech's derived fields read the frame and the pilot, the encounter cannot read the mech's computed values without a two-hop chain, which Craft rejects. So the encounter snapshots. One snapshot at the start, one write-back at the end, and one authoritative source in between.
Two live records would be worse than a snapshot. Pick one and make the handoff explicit.
Writing new triggered instructions
Triggered GM instructions cap at 500 characters of body, and going over means the file is silently never injected. Nothing warns you.
Write them as orders, not explanations. Present tense, imperative, specific. "Check two things on this mech" beats "the GM should consider whether". They fire constantly and they are competing with everything else in context.
Visibility
Keep the pinned set small. In this project it should be the standing rules document and the live encounter, and nothing else. Rules chapters and the compendium are searchable — the GM finds them when a specific number matters, which is exactly when it should.
A project with six pinned chapters has no context left for the fiction.