That's funny, Brigit, the Nite-Ox in Hi-Heels etc. I had tried making a little story for each ten elements, but I think the matching game is simpler and better. But it's worth experimenting.
You must be rich to have 19 sets of encyclopedias. I'd like to see video games that have role-playing a real or fictitious character include tests of knowledge as part of the game. It could involve playing a card matching game for a few minutes.
If you develop your castle elements game, let us have a look at it. Okay?