SFX attatchments

Ok, using one buff, how do I add more attatchments to a unit for a spell? Like, take the soul burn buff. Make Art: Target - Soul Burn, and add a string to the to the Art: Target Attatchment point: "overhead". So now I want to add the Shadow Strike buff FX. Do I add another FX to Art: Target, then add another string to the first Art: Target Attatchemnt Point or do I add it to a new one. Lastly, do i ever need to change the integer Art: target Attachments?

Well from what I've assumed I Think they either Match up via Columns or do something weird.

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Effect 1 | Point 1
Effect 2 | Point 2

I'd think It'd work out like this. But I've never actually tried it myself.