"Because he figured out the cost before he did it," says Gideon. "It basically...okay. So there was this box at the end of this...tunnel. And a field that like...stripped life away? And the only way to get from one end to the other was to draw on a source of thalergy - like...life energy - outside the force field. Pal reckoned he could do it, but it would probably have ended up with permanent brain damage for his Cav, Cam." She rolls one broad shoulder in a shrug. "Either Harrow thought she could get through without that...or she didn't bother to think about it."