ah, so it's like an item combining trigger like in spellcraft. Cool, I have a system in one of my maps that does that but on a small scale, so the system wouldnt be good if u had lots of combos. I'll check ur systems out tho. BTW, what does ur unit pool system do?
I'm not Vex but it's like a custom "Unit-Group" function, however it works for integers and so (because of the return bug) for (nearly) all types!
In the Readme inside his map it says everything!
So far I updated the link with a fix to a bug with gamecaches and campaigns (caused by blizzard) and mostly for the reason of updating the attachment since it got deleted after the attachment apocalypse