trigger · original_research_slots

Hands-On Usage

original_research_slots is commonly used to differentiate treatment of nations based on their base research slot count (i.e., the number of slots at game start, excluding late-game bonuses). For example, you can provide exclusive compensatory focuses or ideas to smaller nations with fewer initial slots. A typical scenario is restricting research catch-up mechanics to nations of a specific size within the available block of a focus or decision.

# In a focus's available condition, only allow nations with few initial research slots to select this catch-up focus
available = {
    original_research_slots < 4
}

# In event trigger conditions, differentiate between major and minor powers
trigger = {
    original_research_slots > 3
}

Synergy

• [add_research_slot](/wiki/effect/add_research_slot): The most common pairing—use original_research_slots to confirm the initial slot count, then employ add_research_slot to compensate nations with insufficient starting slots, avoiding duplicate bonuses to nations that already have high slot counts.
• [amount_research_slots](/wiki/trigger/amount_research_slots): These two form a "base value vs. current value" comparison. original_research_slots checks the foundation at game start, while amount_research_slots checks the runtime actual slot count. Combined use allows you to determine whether a nation has already acquired additional slots through other means.
• [add_tech_bonus](/wiki/effect/add_tech_bonus): Grant technology discounts to nations with few initial slots in specific techs, serving as an indirect compensation for slot disadvantage and logically strongly associated with initial slot conditions.
• [add_ideas](/wiki/effect/add_ideas): Attach different starting ideas to nations based on their initial research slot count, commonly used in game-start differentiation scripts or special rules in historical modes.

Common Pitfalls

1. Confusion with amount_research_slots: Newcomers often mistakenly use amount_research_slots to check "initial" slots, but this trigger returns the current actual value at runtime (including all dynamic bonuses). If checked mid-game, you'll get incorrect results due to bonuses from ideas, focuses, etc. Only original_research_slots truly locks in the static base value at game start.
2. Usage outside COUNTRY scope: This trigger is only valid in country scope. If mistakenly placed within nested blocks of scopes like any_owned_state or unit leaders, the game will error or silently fail. Always ensure the outer scope refers to a country.