trigger · reserves

Hands-On Usage

reserves is commonly used in combat events or decisions to determine whether a combatant still has sufficient reserve forces, thereby triggering reinforcement-related events or modifying combat outcomes. For example, in custom battle resolution mods, you can trigger retreat commands or special campaign events when reserves are depleted.

# Combat event: triggered when attacker's reserves fall below threshold
combat_event = {
    id = my_combat.1
    trigger = {
        is_attacker = yes
        reserves < 2
    }
    ...
}

Synergy

• [has_reserves](/wiki/trigger/has_reserves): Both check reserve status, but has_reserves returns a boolean indicating presence or absence of reserves, while reserves allows numerical comparison. They are commonly combined to distinguish between "existence" and "quantity" judgment layers.
• [is_attacker](/wiki/trigger/is_attacker) / [is_defender](/wiki/trigger/is_defender): Reserve states for both sides of a battlefield typically need separate evaluation. Combined with directional checks, they enable precise conditions targeting one side's reserve count.
• [is_winning](/wiki/trigger/is_winning): Reserve quantity and battlefield victory are often correlated. Together they can describe complex battle states such as "winning but reserves critically low," useful for triggering specific combat narrative events.
• [phase](/wiki/trigger/phase): Combat phase affects the practical significance of reserves. Combining reserves checks across different phases (e.g., shock phase vs consolidation phase) enables more granular battle process simulation.

Common Pitfalls

1. Using outside combat scope: reserves is only valid within COMBATANT scope. Beginners often mistakenly place it in event triggers under country or province scope, causing script errors or silent failures. Always verify the current scope is a combat participant.
2. Logic errors mixing with has_reserves: has_reserves is a boolean check (reserves present/absent), while reserves performs numerical comparison. Inexperienced modders sometimes substitute reserves > 0 for has_reserves = yes. While functionally similar in certain versions, semantically you should prioritize the dedicated boolean trigger to avoid inconsistencies across patch versions.