Zeus would never admit it but watching Apollo - ready to stab himself-kill himself for his friends was the first time he was tempted to pull Apollo out. Surely after seeing what he was willing to do, meant he was learning? Zeus spent so much time thinking and wondering that before he had come to a decision Apollo, an Olympian, one of the few sons he never thought he would have to say goodbye too, shoved that wooden arrow straight into his chest.

Zeus was about to take him to Olympus have him treated there. As much as he wanted Apollo to learn a lesson he couldn't risk Apollo dying. Then Medea hurried to him and immediately treated Apollo, stopping the bleeding, saving him from death.

Zeus wasn't stupid, he knew why Medea had saved him, Medea had announced her intentions that she needed him alive for her plans, but for a split moment, he was thankful for her selfish intentions. They saved his son.

Then Jason died, in the most brutal way possible. Zeus didn't have a loophole like he had with Apollo. Jason's death was already foretold by the fates. He couldn't pull Jason away, and there was no way to turn him into a flower or a tree like he had with Thalia. He could do nothing but watch him die.

Zeus wanted to blame Apollo for bringing him along, even after being told of the prophecy. Yet after watching what Apollo had been prepared to do… he couldn't.

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