Item abilities changed to hero abilities in spellbooks?

[Billy the Cat]

I made a spellbook and wanted to add abilities that were based of the Build Tiny Structure abilities. For some reason those items can't be added and I wanted to know if there was an easy way to add those.

EDIT: HappyTauren helped me solving the problem. I didn't know hero abilites couldn't be added.

 

[jadegolem]

create a dummy spellbook ability called something like "Build Farm Temp".
create an ability that you desire and add it to your last created spellbook. at triggers, make sure you disable the ability for the players. then, create another trigger for example when your hero buys an item. afterwards add the spellbook Build Farm Temp and it will be added to your hero.