I’m sorry but this show isn’t very realistic. If he could do magic Merlin would be rich and married to a gorgeous beauty, in the exact same way as Paul Daniels. I once saw Paul Daniels make a whole car vanish, but on several occasions where this could have saved the day Merlin completely failed to do this and then say “And that’s magic!”
Also Merlin goes and asks a dragon for help, but the dragon never gives straight answers (like talking to a drunk, although John Hurt does the dragon’s voice so I guess it’s kind of accurate), but Paul Daniels would just read the dragon’s mind ( I’ve seen him do it on TV), and then say “not a lot!”
To be honest if I were making a show like Merlin I’d have brought in a proper magician like Paul Daniels of The Great Suprendo in an advisory capacity to make sure it was more realistic.