Couple of Theories

Sorry if any of this is a repeat...

1. Both hunter and Phillip are grimwalkers. "I tried to save your soul" is a reference to the fact that Phillip has continued to suck the life from palismans in order to keep his grimwalker self from deteriorating and has never died while Hunter dies or is killed and restarts with a blank slate every time... this time will be different because flapjack willing gave his life to save him

2. Bat queen was a palisman to the titan...one of her babies will be a palisman to King...implying King has or had 2 siblings?

3. Mysterious figure in the "in between" that appears to Luz is her dad.

4. Luz actually is in the camp. She's fallen into a separate reality to help herself deal with the death of her father and is building a set of characters and stories based on the other kids at camp.

5. Eda was the witch that lured Phillip into the demon realm by first traveling back in time and then through the portal. Flapjack was her original palisman before the curse.