Complex sentence: Perillos believed he would receive a reward for his invention instead, a disgusted Phalaris, who was disgusted by these words, ordered its horn sound system to be tested on Perillos himself.
Split into simpler sentences: Perillos believed he would receive a reward for his invention. Instead, Phalaris, who was disgusted by these words, ordered its horn sound system to be tested on Perillos himself.