Complex sentence: Shocked, Hactar did as asked but designed a small flaw into the device, hoping that when the weapon failed to destroy all of existence, the Armorfiends would see the folly of their ways and turn to a life of peace.
Split into simpler sentences: Shocked, Hactar did as asked but designed a small flaw into the device. It hoped that when the weapon failed to destroy all of existence, the Armorfiends would see the folly of their ways and turn to a life of peace.