I think it’d be great if Kodi could implement Episode specific tags. So the user could tag ‘Christmas Special’ or ‘Halloween Special’ or ‘Crossover Episode’ or any other kind of ‘special tag’ they want to apply and then use it with Smart Playlists to build themed playlists.
I have some Smart Playlists that try to do this, one that filters for every title, series name, or description that contains ‘Christmas’ or ‘Xmas’ but it results in false positives.