Ok so as a mediocre beginner writer, sometimes you do have to tell. Show don't tell is a good rule, but sometimes it is much more natural for a character to explain something or tell something to someone, especially when it's something that would be hard to show. Also you want show and tell to be balanced, sometimes people get caught up in giving no exposition or explanation and so tell nothing and you get a situation like Balan Wonderworld. However, I do think maybe adding a scene where Gale sucks the magic out of an item late at night could be helpful, setting the hook, so his telling feels more justified cause we are asking for him to explain.