I think someone might have asked this question before, but I'm too lazy to reread 100 pages in other places, so I'll ask here: How can I make it so that only the 2nd or 3rd upgrade of creatures can be recruited in a castle? And is it really possible to do this with all races, and not just humans? If so, why don't almost any mapmakers do it? It would be great!;;;;Consider it both a question asked and an idea proposed – for example, pitting the 3rd and 2nd upgrades of demons or elves against each other in a multiplayer map – you can come up with a lot of things.

Added after 21 hours 0 minutes
Okay – I reread another forum – I figured it out – thanks, Menty. The answer was somewhere around page 20, I think.

Added after 1 hour 22 minutes
What should I do if I want to upload a map to the website, but when I go to "manage attachments," it says: "invalid file"? Does that mean I won't be able to upload the map at all?