In Halo Wars how do you level up your guys to higher ranks faster in the game?

[thelaingster]

Everytime I play online in a 1 v 1, when the enemy attack me there guys all have stars round there head, mainly there spartans. how do they level them up to that without me even attacking them? they havnt got any other enemy's to attack so how do they do it?

Cheers

 

[Apotheosis001]

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