So something I've been working on for a while now is a gigantic Fire Emblem fic that acts as an expanded novelization of the Archanea saga, SoV, and Awakening, since they all share not only the same universe, but the same two continents.
I'm currently nearing the Battle at Fort Menedy but there's an issue...there are
three different people claimed to be responsible for the death of King Cornelius and the canon is vague at best. I'm probably just gonna go with the three way combination of Jiol betrayed and set up Cornelius but didn't kill him, Camus and the Sable Order routed his men save for him and Cain, and Gharnef landed the killing blow on Cornelius and stole Falchion.
That way it's more or less compliant with all three answers for "Who Killed Cornelius" and no one can say otherwise.