fvtt-active-effects

To apply temporary buffs and debuffs in Foundry VTT, you configure ActiveEffect data structures on actors or items. This involves defining effect names, changes, duration fields, and statuses to model temporary modifiers across combat encounters.

Duration tracking for Foundry VTT Active Effects uses combat rounds or world-time based durations with defined start points. The system automatically handles cleanup and retires effects when their specified duration expires during gameplay.

Legacy and modern transfer behavior dictate how Foundry VTT Active Effects move from items to actors. Choosing the transfer mode determines whether an effect is applied directly to the owning actor or handled through updated item-to-actor transfer rules.

Yes, you can use CUSTOM mode hooks to implement complex logic for Foundry VTT Active Effects. This allows for advanced effect calculations and customized modifier handling beyond standard additive, override, or multiply modes.

No external dependencies are required to manage Foundry VTT Active Effects. You only need an understanding of ActiveEffect data structures, modes, and duration fields, plus hooks or API usage to initialize and apply effects.

To create an effect like Haste in Foundry VTT, define an ActiveEffect on an actor specifying the AC modifier changes and a duration of 3 rounds. The system applies this buff immediately and tracks its expiration.