Heroic Greek units holding an elevated position (8)
I believe the answer is:
achilles
'heroic greek' is the definition.
'achilles' can be an answer for 'greek' (I have seen 'Famous Greek' mean 'achilles' so perhaps 'greek' could also mean 'achilles'). I'm unsure of the 'heroic' bit.
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for achilles that I've seen before include "Ancient soldier" , "Greek hero with a weak point" , "Mythological Greek hero" , "Ancient Greek with weak heel" , "His heel was his weak point" .)