Countdown timer with UI update using SetTimerByFunctionName

Pattern: Variables: TimeRemaining (float), TimerHandle (TimerHandle). Start: EventBeginPlay → SetTimerByFunctionName(Object=self, FunctionName='OnTick', Time=1.0, bLooping=true). OnTick custom function: Subtract_FloatFloat(A=TimeRemaining, B=1.0) → SetVariable(TimeRemaining) → Branch(TimeRemaining <= 0) → True: ClearAndInvalidateTimerByHandle(Handle=TimerHandle) → OnTimerExpired. UI: GetHUD → CastTo<WBP_HUD> → SetTimerText(Conv_FloatToString(TimeRemaining)). Key: SetTimerByFunctionName output 'ReturnValue' is TimerHandle — save it to clear later.