EDIT: I didn't notice earlier, but Kage had the spark rune on, so I think that is likely what made Viktor miss. I know the spark rune works weirdly in this game, as in my other thread I mention how it won't let another character attack twice if they have a double beat rune, so maybe it alters the character's attack property or something.
I was watching this random video of the Neclord fight at his castle, and interestingly, when the player told everyone to attack, he dodged even Viktor's attack. He then put free will, and Neclord dodged every attack. When Viktor's health was low, however, and the player ordered him to heal, he attacked anyway, hitting and triggering the usual animation and making Neclord vulnerable. I am guessing this is the game's way of preventing the battle from being unwinnable if Viktor faints before he attacks Neclord.
Thus, does anyone know what happens if they enter the battle with Viktor already fainted? Haha, I can imagine this as one reason why they provide the coffins as a free inn to prevent this sort of thing from happening. I don't have a save to test this out, but I would love to see what happens.
On a similar note, does this game use your current HP when entering duels? I am guessing that you would just automatically lose if you tried to enter one with the dueling character having no HP.
Here's the video (battle starts at 18:20)https://www.youtube.com/watch?v=d44KzDVbGQE