Complex sentence: After he failed to kill a dragon, he lost an arm to the beast and was later picked up by the Zaibach, who nursed him back to health under Dornkirk's instructions and fitted him with a mechanical arm.
Split into simpler sentences: After he failed to kill a dragon, he lost an arm to the beast. He was later saved by the Zaibach, who nursed him back to health under Dornkirk's instructions and fitted him with a mechanical arm.