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X4 Modding Wiki

Mod-conflict checklist

This is the pre-publish checklist — for each common mod category, here’s what vanilla content your mod must coexist with. Items ordered by failure cost (top = most dangerous to miss).

Universal pre-publish checks

Section titled “Universal pre-publish checks”

Apply these to EVERY mod regardless of category:

  • Test all 8 game starts — at minimum 60 seconds in each. Any debug.log spam? UI overlay breaks?
  • Test save-resume cycle — save with mod enabled, quit, restart, load. See Wiki: Save compatibility
  • Test DLC absence — for each DLC, disable it and verify your mod still loads. See Wiki: DLC handling
  • Test with no other mods active — your mod alone
  • Test with 1-2 popular mods active (workshop top-list) — known conflicts surface here
  • Check debug.log for Property lookup failed: — silent vanilla breakage shows here
  • Verify content.xml dependencies declared — every DLC requirement / dependency on other mods

If your mod adds factions

Section titled “If your mod adds factions”

Vanilla content to coexist with

Section titled “Vanilla content to coexist with”

Pre-publish checks

Section titled “Pre-publish checks”
  • Faction relations initialized cleanly — see existing factionrelations.xml; don’t leave gaps
  • Faction relations to all 24+ vanilla factions defined — missing entries default unpredictably
  • Faction-internal hostility configured — your faction should have at least one “enemy of” and one “ally of”
  • Add to god.xml seeding — see god.xml docs
  • Add to libraries/factions.xml — race + headquarters + display name
  • Add station macros — without these, no faction infrastructure
  • Test that vanilla wars (ARG_VS_XENON etc.) still work — your faction shouldn’t disrupt vanilla war contact NPCs
  • Test that subscriptions still load — vanilla subscription scripts iterate faction.list — your faction must not break iteration

Conflict hot spots

Section titled “Conflict hot spots”
  • Mods that hardcode faction lists in MD scripts (your faction won’t appear in their UIs)
  • Vanilla gmc_* catalogues that filter by faction (your faction won’t generate missions unless explicit)
  • Vanilla relation-tier checks fire at game start; your faction’s default relations may trigger wrong arcs

If your mod adds missions

Section titled “If your mod adds missions”

Vanilla content to coexist with

Section titled “Vanilla content to coexist with”

Pre-publish checks

Section titled “Pre-publish checks”
  • Mission group declared — see Mission group — without one, your mission shows as uncategorized
  • Mission category set in create_mission — war/dynamic/subscription/assisted_task/story/tutorial/guidance
  • Reward routed through LIB_Reward_Balancing — vanilla economy-consistent
  • Cleanup cue handles event_mission_aborted — see Mission events
  • event_mission_aborted fires on completion too — your cleanup runs on completion path; ensure it’s idempotent
  • Offer location supports .offerlocations — see Generic missions
  • Text references in t/<lang>.xml — missing translations show {page,id} literals
  • Test your mission interacts cleanly with vanilla story arcs — particularly Paranid civil war if your mission touches HOL/argon/paranid

Conflict hot spots

Section titled “Conflict hot spots”
  • Your custom signal-leak missions compete with gmc_dynamic offers
  • Your custom BBS-style missions compete with gmc_assisted_task offers
  • Mission groups overlap: vanilla MG_* constants taken; pick distinct mlog_* prefix

If your mod adds new sectors or changes ownership

Section titled “If your mod adds new sectors or changes ownership”

Vanilla content to coexist with

Section titled “Vanilla content to coexist with”
  • Story arcs — references specific sector macros (cluster_04_sector001 for Paranid story chapter 2, cluster_35_sector001 for derelict, cluster_36_sector001 for Cardinal, cluster_11_sector001 for Paranid Monument, cluster_22_sector001 for Trinity)
  • Game starts — pre-uncovered sectors expected to be specific faction
  • Terraforming planets

Pre-publish checks

Section titled “Pre-publish checks”
  • Don’t replace sector macros referenced by story arcs — grep story_*.xml for cluster_X before changing X
  • Don’t change ownership of cluster_36_sector001 (Cardinal’s Redress) at game start — Paranid story expects neutral
  • Don’t change ownership of cluster_11_sector001 (Paranid Monument) — story breaks
  • Don’t change ownership of cluster_22_sector001 (Trinity Sanctum) — Trinity arc breaks
  • New sectors registered in galaxy macro — without registration, factions ignore them
  • Sector ownership decided — null-owner sectors fall to default behavior
  • Test gates connect properly — orphan sectors break exploration

Conflict hot spots

Section titled “Conflict hot spots”
  • god.xml diff conflicts with other sector mods
  • Vanilla story find_sector calls fail if you’ve changed macro IDs

If your mod changes economy / ware values

Section titled “If your mod changes economy / ware values”

Vanilla content to coexist with

Section titled “Vanilla content to coexist with”

Pre-publish checks

Section titled “Pre-publish checks”
  • Test terraforming UI — costs sensible? Players able to afford?
  • Test mission rewards — generic mission for “deliver 100 microchips” — what reward does vanilla offer with your mod?
  • Test faction economy soak — let game run 2 hours, factions still solvent?
  • Test trade subscription missions — Antigone/Teladi missions still profitable?

Conflict hot spots

Section titled “Conflict hot spots”
  • Ware-value changes propagate through 100+ vanilla calculations
  • Missing ware value definitions (you removed a ware) → vanilla scripts reference non-existent ware

If your mod adds custom game starts

Section titled “If your mod adds custom game starts”

Pre-publish checks

Section titled “Pre-publish checks”
  • Standardize naming: module="my_mod_gamestart_X"
  • Uncover map via md.LIB_Generic.UncoverMap_SectorsAndGates — don’t write custom uncovering
  • Set gamestart.storystate.story_paranid_* flags if your start should skip Paranid intro
  • Don’t break HAT broadcast — vanilla intro arc needs it for non-custom starts
  • Set starting relations explicitly — don’t rely on defaults

Conflict hot spots

Section titled “Conflict hot spots”
  • Multiple custom-start mods overwriting each other’s setup
  • Custom start that doesn’t set storystate flags → vanilla Paranid arc tries to start mid-game

If your mod changes NPC spawning

Section titled “If your mod changes NPC spawning”

Vanilla content to coexist with

Section titled “Vanilla content to coexist with”
  • Story arc anchored NPCs (Cardinal, Boso Ta, Reen, etc. — see Story arcs → Persistent characters)
  • Subscription contact NPCs (war contacts, mentor RM_SETA)
  • Terraforming Skipper

Pre-publish checks

Section titled “Pre-publish checks”
  • Don’t fill all tag.npc_* slots on key stations — story NPCs need slots
  • Spawn NPCs with $slottags=[tag.npc_generic] — vanilla compatible
  • Use add_anchored_object for persistent NPCs — paired with cleanup
  • Don’t destroy_object on actors you didn’t create
  • Test that vanilla Cardinal/Boso Ta/Reen still spawn — your mod’s bulk NPC spawning may starve them of slots

Conflict hot spots

Section titled “Conflict hot spots”
  • NPC Placement Manager has finite slot capacity per station
  • Multiple character mods spawning at same station = race / lost spawns

If your mod adds tutorials

Section titled “If your mod adds tutorials”

Pre-publish checks

Section titled “Pre-publish checks”
  • Register in md.Tutorial_Global.$completed_tutorials — see Tutorial missions
  • Don’t re-offer completed tutorials — track completion flag
  • Use signal_cue md.HUD.ShowGuidance for prompts — vanilla mechanism
  • Patch-migration for completed_tutorials list — older saves don’t have your tutorial id

Integration with existing mods

Section titled “Integration with existing mods”

If you’re publishing alongside common mod stacks, check compatibility with:

Common modWhat it changesYour mod’s risk
DeadAir modsEconomy + scriptsEconomic conflicts; mission reward math
VRO (Variety Rebalance Overhaul)Ship balanceCombat-tuning conflict
SirNuke’s Hotkey ManagerUI hotkeysUI hook conflict
Mules, Improved TradeTrader behaviorTrade subscription interference
Sector SatellitesNPC spawningNPC slot pressure
Civilian DensityMass trafficgm_killmasstraffic mission target population

(Where applicable — your mod’s manifest can declare an optional dependency or recommend mod load order.)

When something breaks

Section titled “When something breaks”

If your mod ships and players report breakage:

  1. Get debug.log — players send Documents/Egosoft/X4/<save>/debug.log
  2. Search for Property lookup failed: near your mod’s namespace
  3. Search for event_mission_aborted in unexpected places — mission cleanup running for the wrong cause
  4. Check add_anchored_object leaks — your mod’s actors persisting after they should despawn
  5. Walk save through every vanilla story arc — verify each still fires correctly

See Wiki: Debugging strategies for the diagnosis ladder.

Section titled “Related”

The cost of a conflict checklist run is ~30 minutes. The cost of a broken save report from a player is ~3 hours of debugging + a 2-star Workshop review. The arithmetic recommends itself.