The Mer doesn't seem phaseds by Gwen'd knowledge, but nods, and adds - "And when I deliver, where is what I was promised? You turn on me with your poison tongue? You asked for my Art, I grant it to you now!"
Aerissa makes a sharp gesture, slashing with a barbed spine at the translucent fishing wire strands that suspend her ice star in midair to twinkle merrily. A turn, and she shoves it, letting it go crashing into the Selkie, the weight and momentum of many, many pounds of ice bearing down on his, and shattering.