The Eidolon Teralyst is a towering, biomechanical entity with a skeletal, angular frame covered in glowing, pulsating energy veins. Its body is composed of a dark, metallic exoskeleton with intricate, organic-like patterns etched into its surface, giving it a weathered and ancient appearance. The Teralyst features elongated limbs, a hunched posture, and a distinctive, luminescent core at its chest, surrounded by floating, fragmented armor pieces that emit a faint blue glow. Its head is crowned with antler-like protrusions that crackle with energy, and its movements are accompanied by eerie, resonant sounds.