Starcraft – What attack is used against the Colossus

starcraft-2

The Colossus is unique in that it can be attacked by both ground attacks and air attacks. Some units, however, can attack both air and ground, and use a different attack for each – for example the Thor has completely different ground and air attacks.

When attacking a Colossus, which attack does the attacking unit use? Ground or air? And why does it use that attack?

I think I actually already have an answer which I will post below, but I would love to hear more insight as to how it is determined and why.

Best Answer

So the secret to this conundrum can be found by examining the Goliath, and the Goliath merc.

The Goliath Merc uses ground while the Goliath uses Air. alt text alt text

So why doe the Thor use ground?

If we actually look at the Thor we see that the Thor actually acquires with its weapons based on angle.
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On the Goliath and Goliath merc, these values are set to distance. Since the Thor can use angle to prioritize (Colossus and Goliath are both ground), it does. Since the Goliath can't (distance is identical), it defaults to the order its weapons occur.

Finally, this explains the Scout:
alt text