Function: AddTemporaryImmunity(Spawn, ImmunityType, DurationMS)
Description: Grant an immunity for a positive duration in milliseconds.
Parameters:
Spawn: Spawn - Required Entity receiving the immunity.ImmunityType: UInt8 - Immunity ID; use a namedIMMUNITY_TYPE_*Lua constant. Damage immunities use IDs 11–25.DurationMS: UInt32 - Positive duration in milliseconds.
Returns: None.
Behavior: Reapplying a timed immunity can extend its expiry. Expiry does not remove independent direct or spell-owned grants. No current spell is required. See the immunity table and damage behavior.