I don't know why everyone says that the Castle faction is overpowered. Maybe I'm just not playing well and don't understand... Oh well... In my opinion, their units are a bit expensive at the beginning. The 7th level unit is weak. However, the Psionicists are really powerful, and the 5th level unit is also good – a tanky unit. I like the 4th level unit only because it's fire-based. The Fairies are good at the beginning, I admit. The 2nd and 3rd levels are good as starting units, like archers, but then they become quite weak.