The echo started properly on the second day. First it was only footsteps. Then it was Cal’s voice repeating the last three words of every sentence he spoke, delayed by a full breath. He found it hilarious until the echo began answering questions he had not finished asking. Sela recorded the phenomenon with scientific glee and then nearly walked off the path when her own mutter of “interesting” came back as “interesting danger ahead.” Kael tested it by shouting insults at the mountain. The mountain shouted them back with improved timing and, once, better vocabulary. He declared the mountain a worthy opponent. The fun ended when the echo turned physical. Around a sharp bend the path duplicated itself—two identical trails branching for twenty paces before snapping back into one. On the fa

