Exactly
One spellbook per building
This way when you build it, it builds only that specific one in that spellbook
Here
THE first spell book, is for the user to see
Then, you wanna build buildings, SO
You create ONE MORE spellbook, give it a random Order ID
Add a "Build Tiny Castle" (or whatever your custom build spell is)
To the last created spellbook
So now, you have the spellbook that shows up to the player
One inside of that
And the custom abile inside the second one
Now we create YET ANOTHER spellbook
Add your second build spell to it
NOW
When the user clicks the spellbook thats shown to him, there are two spellbook icons, when he clicks either one of them, there is ONLY ONE build ability in it, BUT he can use it w/o worrying about it not working
The point of the second level of spellbooks is to separate the build spells
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I'm not 100% sure if you can, but you can use a GUI function called "Force Key", so when the user opens the second layer of spell book, it automatically starts the spell inside, making it *seem* as if there is only one spellbook
I'm not sure, but maybe you can check for the spellbook open using starts the effect of an ability, but I really don't know
The user could still technically see the second menu if they click "cancel"
Anyway, the point is it IS possible to separate the building spells without messing too much with the Order ID's
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I like Dragoons way of doing it, simply adding the desired spell
But, he wasn't 100% clear on how to do it