Can an Immortal really shoot over higher ground?

Question

As far as I know you can only shoot on higher ground if you have sight (like if you have an Observer flying near) but how come this Immortal was able to shoot on higher ground even if he has no sight?

Answer 1

The reason for this is because the colosus is counted as a flying unit in this case, and low ground units can see high ground flying units when they attack

High ground

• Any Unit on high ground can see any unit on the low ground.
• Units on the high ground that attack will reveal their position.(but not necessarily grant vision)

Low ground

• Ground Units on the low ground can not see ground units on the high ground.
• Ground Units on the low ground can only see air units on the high ground if the air unit has attacked them.
• Ground Units at the bottom of a ramp have reduced vision up the ramp.

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