Fanon Alert!
This article is of something that's FANMADE, and users own it instead of NinjaKiwi.

Leech bloon leeches an upgrade from the weakest tower as of then when it reaches the end! It, otherwise, is like a Black Bloon without the bomb immunity. It CANNOT leech anything from non-living towers, robo-monkeys, or sun gods, or their upgrades.