I really love the "Escalate to Battle Phase" completion sound you hear in Company of Heroes. You just know shit's goin' down now.
I also really like to hear when my little line infantry guys shout "Ge fyyyyr!" in Empire: Total War, followed by that lovely choir of musket blasts. Again, shit's goin' down, and it's the enemy.
Then, there's the TF2 Announcer, at least while you're doing well.
But above all, I love the victory fanfare for the Soviets in Red Orchestra 2. It's... So beautiful...
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