heros that build

this may be a stupid question.....i tried to figure it out

how do u make it so a hero can build buildings..... thers no field for that.

Last I checked the only way to do this was to manually edit the unit data, but it doesn't really work anyways because the buildings it can build and the abilities it can learn end up on the same card and it looks really weird. If you want to do it anyway though, you just need to add the stat related and hero ability fields to a peon's modification list and it will become a hero (as in it shows the portrait and lets you edit those fields in the editor).
If you don't know how to do that, find a tutorial that teaches u about the unit modification file in the w3m (like zepir's format tutorial)