Reach the exfil chopper with 1 minute and 30 seconds or more remaining on the clock. [Bronze / 20G]
This can only be done in Extinction Mode. To unlock extinction you need to finish the first mission of the campaign on any difficulty or reach level 5 in multiplayer. It's basically an alien mode where you have to use a drill to destroy alien hives.
You must destroy all 12 hives to unlock the computer that initiates the exfiltration countdown. The computer will spawn right next to the last hive and all players have to activate it simultaneously. You do now have 2 minutes and 30 seconds to get back to the helicopter in the starting area.
Meteorite barricades will block your way, but they will automatically fall apart after 30 seconds and there are only 2 of them. You will also be attacked by many Rhinos. They are heavily armored, so use armor breaking ammo to take them down. Fully upgraded sentry guns will come in very handy here. They distract and at the same time damage the Rhinos. If your health gets low, deploy fully upgraded armor vests. Armor can be especially useful if you are running and a Rhino attacks you from behind. So every player should have armor vests in their loadout to avoid going down.
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