Yep, Helena was Puck all along. Damn Puck, always causing trouble. Why the name Helena? She's one of the young lovers in A Midsummer Night's Dream. It seemed appropriate.
I've been anxious to do this reveal for a while now. It took a bit to figure out how to show it - I kept seeing it animated and not as a still image. I ended up drawing Helena and Puck out individually and then adding an outer-glow to each of their lines. It seems to have worked.
You can see the full spread here.