In Terminus, there are 4 locations where you can obtain a free perk:

• Perk 1
  • Between the Bio-Lab and the Docks, you can open 10 crates underwater. Once you have opened all of them, you will be rewarded with a perk.
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• Perk 2
  • The second perk is located in the Bio-Lab. You will find cages with zombies inside. Kill them and move to the next round. Then, you will notice more enemies in the cages. Kill these as well and proceed to the next round. Finally, you must kill the Manglers in the cages. Once you’ve completed this, you will receive the free perk. Keep in mind that you must complete these steps in the same round and not use any power-ups like the Nuke.
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• Perk 3
  • Look for an island on the map where you can see glowing yellow spores. Shoot them and kill the parasites that appear. Once you have shot all the spores and successfully completed this step, you will hear a sound. This indicates that you have completed this step. Repeat the process two more times. After completing this, head to the sea caves, where you will find another glowing spore. Shoot it down, and you will be rewarded with the free perk.
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• Perk 4
  • The fourth perk is located on Crab Island. On this island, you will find a wooden crab cage. Throw a grenade at it, and the cage will fall and break. You will now see some dancing crabs. Knife these crabs, and a mini-game with a 30-second timer will begin. If you successfully complete the game, you will receive another free perk.
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