Plot missions

The word “plot” is overloaded in X4 modding. There are three distinct things with “plot” in their name, and they are not the same system. This page disambiguates.

The three “plot” concepts

What people call “plot missions”	Actual implementation	Real page
Main story arc (Paranid plot, Buccaneers plot, etc.)	story_*.xml	Story missions
Claim a sector plot (territorial expansion missions)	gm_claimplot.xml (Generic template)	This page
The plot.xml script	Actor-persistence storage cue, NOT a mission system	This page

”Plot” as sector claim — gm_claimplot.xml

The gameplay concept “claim a plot of space” (= establish sector ownership) is implemented as one generic mission template — md/gm_claimplot.xml (739 lines).

md.GM_ClaimPlot.Start
├── Do_Not_Start_Mission (early bail)
└── Do_Start_Mission
    ├── With_Offer
    │   ├── CreateOffer
    │   ├── Offer_Management (ref md.GenericMissions.OfferMission)
    │   └── Offer_End
    └── BriefingStarted
        ├── DisplayCutscene
        ├── MissionAccepted
        │   ├── ActivateImmediately
        │   ├── ActivateOnCondition
        │   └── ActivateMission
        │       └── ClaimPlot_Ref (ref md.RML_ClaimPlot.ClaimPlot)
        └── BriefingStopped

It uses the standard generic-mission lifecycle from Generic missions — With_Offer / BriefingStarted / MissionAccepted / ActivateMission — and delegates the actual claim-plot work to rml_claimplot.xml.

What the mission does

1. Offer phase: A faction representative offers “Claim Sector X for our faction”
2. Accept phase: Player chooses to accept, briefing plays
3. Activate phase: Mission becomes active; player must satisfy claim conditions
4. Claim phase (rml_claimplot.xml): Verify ownership criteria — own stations in sector, sufficient territorial presence
5. Complete: Sector ownership transfers to faction (typically player’s faction for player-side claims)

Modding context — sector ownership change

This is the only vanilla mission template that changes sector ownership. If your mod wants to:

• Add a new sector-claim variant (e.g. “Claim sector by destroying 50% of enemy stations”)
• Reuse the claim-plot infrastructure in a custom mission

reference md.RML_ClaimPlot.ClaimPlot from your mission. The library handles the sector ownership transfer + map repaint + faction relation cascade.

”Plot” as actor storage — plot.xml

md/plot.xml is 7 lines total:

<mdscript name="Plot">
    <cues>
        <!-- This cue is used as a storage area for persistent NPCs that are used in story missions,
             so that multiple instances of the same actor are not created when two missions that
             use the same NPC run simultaneously -->
        <cue name="Actors" />
    </cues>
</mdscript>

It is NOT a mission system. It is a shared namespace for cross-mission actor persistence.

What modders use it for

When two story missions both reference “the Cardinal” character, they can’t both create_actor — that produces two Cardinals walking around. Pattern:

<!-- In your story mission: -->
<do_if value="not @md.Plot.Actors.$Cardinal">
    <create_actor name="md.Plot.Actors.$Cardinal"
        race="paranid"
        ... />
    <add_anchored_object
        object="md.Plot.Actors.$Cardinal"
        reason="PLOT_ACTOR_CARDINAL"/>
</do_if>

<!-- Then use: -->
<set_value name="$MyCardinalRef"
    exact="md.Plot.Actors.$Cardinal"/>

The first mission that needs Cardinal creates him; subsequent missions reuse him. The Actors cue is just a named bucket for these globals — md.Plot.Actors.$Cardinal.

Why it’s a separate file

By living in its own plot.xml, the storage cue activates at game start regardless of which story plays — actors can be created lazily by any story that needs them.

”Plot” as main story arc

When players say “the plot” colloquially they mean the main story arc the player follows (Paranid plot, Welfare research plot, Buccaneers plot). These are implemented in story_*.xml, not in plot.xml. See Story missions.

Common gotchas

• ⚠ plot.xml is NOT the main plot script — it’s a 7-line actor storage cue; the main plot lives in story_*.xml
• ⚠ gm_claimplot is a Generic template, not a separate category — it follows the Generic missions lifecycle
• ⚠ rml_claimplot performs the actual ownership change — if you customize claim conditions, reference md.RML_ClaimPlot.ClaimPlot
• ⚠ md.Plot.Actors.$X is global — name collisions between mods are silent corruption; always prefix $mlog_X style

Code references (vanilla)

Concern	File
Claim-plot mission template	gm_claimplot.xml (739 lines)
Claim-plot reusable library	rml_claimplot.xml
Persistent actor storage	plot.xml (7 lines)
Sector ownership change	rml_claimplot.xml — search for set_owner sector=

Related

• Story missions — main-plot narrative
• Generic missions — the layer gm_claimplot uses
• Sector — sector ownership accessors
• Faction — set_owner action
• Mission events — event_mission_aborted etc.

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If your mod docs say “adds new plot missions”, be specific about which “plot” — vanilla uses three different things with that name. Future-you and future-modders will thank you.