Season 3 was Awful -possible minor spoilers
Wow, did that show go down hill. You just know that when most of the major actors bail, something is up. Unfortunately, with just Phil, Belore and the new bumbling wizard nothing good could happen. Even Phil was replaceable, and Belore was annoying to begin with. How many times can you turn into a skull and come back? I mean really!
The main downfall of the series I think is that it was based on a repetitive formula that got tired. Even the second season dragged for that reason. The kids must have gotten tired of chanting "Rothgo" multiple times per episode like a get out of jail card, and you knew that Belore was going to deny the Nitus in every episode until the last. Sometimes the best thing when you paint yourself into a corner like that is to quit while you're ahead.
I loved this series as a kid, and still have many fond memories of it. Now that I watch it again, I'm reminded of a board game with random rules that slap you back to Go without collecting your 20 bucks just when you think you were ahead. Ah, well they don't make shows like that any more.