What happens when they meet?  
Do they both take the other’s form simultaneously?

Actually,@The Toaster Repair Pony, the Zerg Changeling does have it’s uses. It’s just that those uses are hard to make use of in-game, due to the attempted balancing of it’s time limit. Make it go boom like a Baneling, and suddenly it’s going to be OP, because it’s a Baneling that your enemies can’t auto attack. Same goes for everything else it could be used for. The idea is nearly impossible to balence in game because surveillance that the enemy has to target manually is hard to deal with. Really, the only way to make it useable and balanced is to make it permanent and have an almost obvious tell when in range of a detector, like being off color, or a visible outline, but still needing to be manually targeted. Even then, it might be OP due to the fact that it’s going to stay in the nearest blob of units at all times.

Oh no,@Vree, Zerg changelings are just short-lived Give them an upgrade, like being a replacement for Spawn Broodling, would make them OP. In lore, give them the capacity to morph weapons to make them useful.

Yet another reason why I’m surprised there’s not more changelings-as-zerg stuff.

One is a emotion-eating parasite, and the other is a waste of biomass.

or, yknow