Description: Kill 5 enemies within 10 seconds, using any rifle
How to obtain:
If you have not unlocked this achievement during the main storyline, it is best to replay the Acropolis, since you can find a dozen-or-so opponents here, right after you start the stage. After the first cutscene, alarm opponents in the yard to your presence, thanks to which they follow you, clustered together. This will make your job easier, because 5-8 opponents will follow you, while close to each other. Equip any rifle (the assault rifle would be best) and start shooting at the enemies.