Raffinery, Extractor and Assimilator ability

[operation3000]

hello
i'm looking for an ability for a building that will make it act as like as a gold mine.
But the problem, it must be built on another specified thing. So, if someone can tell me what must be this thing and how to make the building only buildable on this thing, i should be able to continue my map
When i said what must be this thing, i meant Destrucible, Ward, Doodad...
I want to make it act like a reffinery or an extractor or an assimilator in starcraft, the building that allows you to drain gaz^^
thanks

 

[greasontim]

Requires some triggers which I'm not in the mood to do (Almost been up for 24 hours)
Make the build recueable with a upgrade to change it into the building that you build on it
and give that upgraded building the ability to give gold

 

[mckill2009]

create 2 units and a custom ability, when you fire that ability on unit 1 create the unit 2 on top of unit 1, and create a trigger that as long as unit 2 is alive you will generate gold...btw, unit 1 & 2 set the movement to zero/none, and turn off collisions...

and for the model, just edit whatever you like...