I had Scylla down to 19 health on the final node and the game started bugging out. My monsters were attacking to the left instead of straight in front. Scylla's monsters were attacking to the right and even started attacking twice! Anyone else noticing the game cheating to keep scylla alive?
After playing for seven years I finally figured out the story/plot of this game. (Spoiler Alert, not really) At the title screen the little sister in the tower kills everyone at a wedding "feast". The only survivor is the groom who then seeks revenge by throwing anything and everything he can muster to attack the castle. I no longer feel so good about myself defending the castle when I know I'm protecting a murderous psychopath. We're the bad guys.
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You're the soldier and you need the rifle :)