There are targetable balloons in atleast Forest Haven, Fort Blackstone, and City of Oasis.

Can they be popped yet?

Maybe with one of the mega-combos?

Nature Strike + Hellscream
Shatter + Break Armor
Crushed + Drain Life.

Ugh I'm also wanting to find a dev, for world dominance/antennae power! :3

Join me in figuring this out, add my main "MyLovely" to your friends list!