Complex sentence: Kallisto, horrified and about to die because Yemo was very strong, asked for help from the demigod Heracles, who\\ gave Kallisto the skill to move his muscles harmoniously so he could defend himself with grace.
Split into simpler sentences: Kallisto, horrified and about to die because Yemo was very strong, asked for help from the demigod Heracles. Heracles did not ignore his pleas and gave Kallisto the skill to move his muscles harmoniously so he could defend himself with grace.