So obviously, it should be used against mothership/carrier/BCs and stuff like that, is it still good against smaller units?
Also, as I've just discovered, the corruption ability works against all units, not only air (!), which is awesome, and brings up other possibilities like corrupting thors or ultralisks, but what about other units?
Other corruptors, mutalisks, vikings, stalkers? Smaller things like marauders or helions?
Edit: And of course, I don't think it is ever viable to base your strategy on building a lot of curruptors to use the corruption ability if you know that the opponent goes for stalkers for example. My question is about whether to use the corruption ability if you "already have" corruptors, built for whatever purposes.
Best Answer
This ability is good against almost everything - just use it on every enemy unit as long as you can. Just make sure to prioritize it - meaning, first corrupt the biggest, higher-hp targets, then the medium-hp ones, then the smaller ones and so on.
Why? Because on the one hand, battles usually do not last longer than the cooldown on corruption, so there's no point saving the ability for later. On the other hand, almost always the down-time between battles - or, alternatively, the time it takes the enemy to rebuild his heavy units - is longer than the time it takes the ability to recharge anyway.
Granted, corrupting individual marauders or phoenixes is pretty silly - but as long as you can, and every bigger unit is already corrupted, why not?