Friendly buff spell with a missile?

Is there such a thing among default wc3 abilities?

I'm sure you should be able to make Acid Bomb target allies. You can easily make the buff appear friendly (green text in tooltip) by using colour codes in the buff name.

Alternatively, use a triggered missile that applies the buff when it reaches its target.

Acid Bomb it is. Thank you.

Huh, I never thought of that. That's kind of brilliant.

It's not that good. I think dispel abilities will still treat it as a negative buff, so if you have that in your map you can't use this trick. Of course, you could always use a buff system and trigger your dispel, but in that case you wouldn't be using a spell like Acid Bomb to begin with.