It didn't click for me that this was the same evil wizard from 1 day until I got the dragon water in my throne room. And I was like wait a second, dragon water...spirit swap...!!!
For the level 14 Last Ninja. Use balista's at both entrances. I had 5 at each end. As long as they fire before he smoke bombs (ie. sell any hunter dens you have there.) they'll nuke him for you to 5 upgraded meteor him.
Here's a hint for the third treasure room. you place both your one way gates next to each other, and one of them next to the arrow trigger plate. Hope this helps. :)
First and foremost, regardless of any choices. Build your town's garden. By the end of the game you'll save so many weeks of kicking around your house.