gistfile1.txt

        //'Block' is a Textblock in my form

        //All of this method works perfectly fine
        private void AddLine(string text)
        {
            if (Block.Inlines.Any())
                Block.Inlines.FirstInline.Foreground = Brushes.Black;

            var line = new Run(text+"\n") {Foreground = Brushes.Black};
            Block.Inlines.Add(line);
            Scrollbar.ScrollToBottom();

            var fadeIn = new DoubleAnimation(0.0, 1.0, new Duration(TimeSpan.FromSeconds(3))) {AutoReverse = false};

            Storyboard.SetTarget(fadeIn, line);
            Storyboard.SetTargetProperty(fadeIn, new PropertyPath("Foreground.Opacity"));

            var board = new Storyboard();
            board.Children.Add(fadeIn);
            board.Begin();
        }

        //This method animates successfuly, but the event function is not successfuly fixing opacity.
        private void Wipe()
        {
            var fadeOut = new DoubleAnimation(1.0, 0.0, new Duration(TimeSpan.FromSeconds(3))) { AutoReverse = false };
            Storyboard.SetTarget(fadeOut, Block);
            Storyboard.SetTargetProperty(fadeOut, new PropertyPath(OpacityProperty));
            var board = new Storyboard();
            board.Children.Add(fadeOut);
            board.Completed += (obj, events) =>
            {
                Block.Inlines.Clear();
                Block.Opacity = 1.0; //Set a breakpoint here and it did indeed get hit, but it got set right back to 0 anyways?
            };
            board.Begin();
        }