07 — Tuning guide: recipes, testing, and event scripts¶

Index · Basics

This chapter collects the common balance changes and shows the smallest correct way to make each one. All examples are written as mod files that load the previous version and modify it (00 §3).

1. Workflow¶

Create MODS/<YourMod>/info.txt with ICBM MOD "Your mod".
For each game file you change, create the same path in your mod and start it with USE PREVIOUS "<same path>".
Change existing entries with MODIFY; create new ones with a new ID (or COPY for units).
Start a skirmish: an "unknown keyword" error means a typo stopped the file (see 00). Then check your changes in game.
Test with the Cheats build: Shift + T researches the queued technologies at once, Ctrl + click in the production panel builds a unit instantly, Shift + 0 … 9 switches faction.
Multiplayer: every player needs the identical mod set; the game compares CRCs of the loaded data.

2. Recipes¶

Make a unit tougher or cheaper¶

USE PREVIOUS "Units/Units.txt"

[UNIT] "Destroyer" MODIFY
  Power 12                 // hit points
  ProductionCost 7

Remember that AutoRepair speed is inversely proportional to ProductionCost, so a cheaper unit also repairs faster.

Change a weapon's range only after research¶

USE PREVIOUS "Units/Missile_defs.txt"

[MISSILE] "SAM" MODIFY
  delete ImprovedBy "SAM_Mk2"            // drop the old upgrade…
  ImprovedBy "SAM_Mk2" Set Range 450     // …and give a new one

For a chain of upgrades use Set in increasing order; later known techs are applied later and win.

Make nukes more or less deadly for cities¶

Edit the explosion, not the missile:

USE PREVIOUS "Units/explosion.txt"

[EXPLOSION] "nuke_100" MODIFY
  FullEffectRange 7        // was 10: full-effect area −51 %
  Range 45                 // was 60

Casualties scale with the covered area (radius²) and only slowly with Damage (see 03 §3). MinCasualties adds a flat number per city hit.

Make a missile harder to intercept¶

[MISSILE] "ICBM (1M Light)" MODIFY
  CanBeIntercepted 0.25    // chance that an interceptor hit counts
  Power 2                  // needs two counted hits of a Damage-1 interceptor

FakeHeads n "decoy" and higher Speed also help. The opposite knobs on the defence side are the interceptor's Precision, its explosion Range/Damage, Launch per salvo, and MinMissilesPerTarget/MaxMissilesPerTarget.

Make a unit stealthier against radar¶

USE PREVIOUS "Units/Units.txt"
[UNIT] "Bomber" MODIFY
  Modifier "Bomber_Stealth_Bonus_Modifier_1" value 0.6          // tag the unit type (tag = a tech ID)

USE PREVIOUS "Units/Radars.txt"                    // (in Units/Radars.txt of the mod)
[RADAR] "STD Long Wave" MODIFY
  AffectedBy Unit "Bomber_Stealth_Bonus_Modifier_1" Range value   // range × 0.6 against tagged units

The effect is active only while the unit's owner knows the tech Bomber_Stealth_Bonus_Modifier_1.

A buff aura (e.g. faster reload near a command post)¶

[MISSILE] "Command_Aura"                     // Units/Missile_defs.txt (new, illustrative)
  Tech "M_Command_Aura"
  Type "No Attack"
  Icon "Units/Images/Missiles/Buff.png"
  Explosion "No_Explosion"
  Range 150                                 // aura radius
  Hidden Yes
  HideRange No
  Switchable ON
  CanBeLimited false

[UNIT] "Command_Post" MODIFY                 // Units/Units.txt (illustrative unit)
  Weapon "Command_Aura" 1                   // the aura works while the weapon is switched on

[UNIT] "Army_Division" MODIFY
  ImprovedBy InRange "Command_Aura" Modify Weapon "Land Forces" Time 0.8   // 20 % faster reload

A lasting debuff (EMP-style)¶

[EXPLOSION] "My_EMP"                         // explosion.txt
  Damage 0
  Range 80
  FullEffectRange 80
  LastingEffect 3600 StringID 1908           // 120 "seconds"
  TriggerResponse No

[UNIT] "VirtualCity" MODIFY                  // Units.txt
  AffectedBy Explosion "My_EMP" Production 0.5

Faction-specific unit¶

[TECHNOLOGY] "U_My_Unit"                     // tech.txt
  Name "U_MY_UNIT_NAME"
  Description "U_MY_UNIT_DESC"
  Parent "Your_Research_Tech"               // the research tech that unlocks it
  Parent "PREFIX_EA" HideLink                // only factions using the EA model set

Move a unit in the tech tree¶

Change which research tech has its zero-cost unit tech as a child:

[TECHNOLOGY] "Old_Parent" MODIFY
  delete LeadsTo "U_My_Unit"
[TECHNOLOGY] "New_Parent" MODIFY
  LeadsTo "U_My_Unit"

Global knobs¶

Want	Where	Setting
All units faster/slower	`Units.txt`	`GlobalSpeedModifier 1.2`
All missiles faster/slower	`Missile_defs.txt`	`GlobalSpeedModifier 1.2`
All reloads slower	`Units.txt`	`GlobalMissileLaunchDelayModifier 1.5`
All aircraft launch slower	`Units.txt`	`GlobalAircraftLaunchDelayModifier 1.5`
Cities easier to hit	`Units.txt`	`GlobalCitySizeModifier 1.2`
City capture time	`Units.txt`	`CityOccupationMultPerPercent`, `Min/MaxTimeToOccupyCity`
Less pollution	`explosion.txt`	`PollutionMultiplier 0.25`
Research cost per level	`TechLevels.txt`	`NextLevelMultiplier 1.3`

3. Event scripts and unit definitions¶

Mission event scripts (EVENTS/*.txt, see the ICBM – Events script reference) cannot change the numbers in these files, but they interact with them through technologies, weapons and unit types. The robust pattern is: put the balance change in the data files behind a technology, and let the script grant the technology.

Script feature	Connects to
`GRANT_TECH(FactionID, "tech")` (also a set of techs)	Grants the tech and its unknown parents without triggering `Researched` events. Anything behind `ImprovedBy "tech"` switches on. Works for `CanBeResearched No` techs; never for techs parented to `BLOCKER`.
`TECH_AVAILABLE`, `GET_FACTION_TECHS`, `TECH_NAME`	Tech IDs from `tech.txt`.
`ON Researched "tech" BY …`, `ON Tech_Available "tech" …`	Tech IDs.
`Build "Unit_ID"`, `CREATE_UNIT`, `CREATE_GROUP`, `ANY "Unit_ID"`, `SELECT … TYPE == "Unit_ID"`	`[UNIT]` IDs; `CLASS` compares with unit classes (`Ground`, `Naval`, …).
`Disable` / `Enable Missiles NUKE\\|BIO\\|CHEM\\|EMP\\|MASS DESTRUCTION\\|GENEVA "cat"\\|AI_CATEGORY "cat"\\|"missile"`	Explosion `Type`s, `TriggerResponse` (= mass destruction), Geneva and AI categories, missile IDs. Only missiles with `CanBeLimited Yes` are affected by category bans.
`Unit X Weapon_Use "missile" Never\\|Always\\|WhenAttacked…`	Overrides a weapon's `AutoEngage` for one unit.
`Weapon_Switch "missile" ON\\|OFF`	Turns `Switchable` weapons on/off.
`SET_WEAPON_CONFIG`, `GET_WEAPON_CONFIG`, `WEAPON_CONFIG_AVAILABLE`	Config names from the unit's `Config "…"` lines.
`WEAPON_RANGE`, `WEAPON_YIELD`, `WEAPON_GENEVA_CATEGORY`, `WEAPON_AI_CATEGORY`, `HAS_WEAPON`, `NUM_AVAILABLE`	Read the (modified) weapon values and categories.
`RANGE`, `SAFE_RANGE`, `SPEED`, `RADAR_RANGE`, `ATTACK_RANGE`, `HEALTH`, `HEALTH_PERCENT`	Read unit values after tech modifiers.
`ON Exploded "missile"\\|NUKE… IN …`, `ON Damaged … BY "missile"`, `ON Launched "missile" …`	Missile IDs and explosion types.

Example — a scenario reward that unlocks a hidden upgrade (the tech has Points 100 and CanBeResearched No in tech.txt; its effect is ImprovedBy "Scenario_Railgun_Bonus" Range 1.25 on the railgun):

BLOCK GrantRailgunBonus()
  GRANT_TECH(SelfID, "Scenario_Railgun_Bonus")
  Message "Railgun range increased" Position TopLeft
END

ON Mission "Secure the lab" SUCCESS GrantRailgunBonus()
END

(Mission "…" must match a mission name declared in the map's ScenarioInfo.)

4. Before you publish¶

The game starts without "unknown keyword" errors.
Every new object has a Tech with Name/Description strings in every language file you ship.
New weapons are in some unit's config, new units are buildable (CanBeBuilt, class, tech reachable), new aircraft are hosted somewhere.
IF markers wrap whole entries.
You used MODIFY + USE PREVIOUS wherever possible, so your mod combines with others.