You already have 30,000 gold! I think you have enough gold, Baron.
Actually that's a good idea. I might be able to add it to the web version at least. I'm having issues trying to update the app right now.
There is no wiki. If you want to make it, that could be cool! I was planning on making a web page for each defense and for each castle, but I barely have time to even code now since I'm trying to draw art now that I can't afford my artist anymore. Might not look as cool but lots of new stuff is coming.