How to get Refined and Flawless Aetherium Crystals to unlock tier four and five skill upgrades in Call of Duty: Black Ops Cold War Zombies

Get a good start on grabbing those new skill levels in Zombies.

Image via Treyarch

Call of Duty: Black Ops Cold War’s season two brings tons of new content to the game in both Multiplayer and Zombies. On the Zombies side specifically, two new tiers are being added to the skill paths meaning players will be able to increase further the usefulness of their perks, weapons, ammo mods, and field upgrades. These upgrades are even more impactful than what we’ve seen before, making them worth the effort to unlock. To unlock them, though, you need to gather two new currencies in the game. Here is how to collect Refined and Flawless Aetherium Crystals and unlock the tier four and five skill upgrades in Call of Duty: Black Ops Cold Wars Zombies.

Screenshot by Gamepur

Getting your hands on the new Aetherium Crystals will be a little more difficult than the original Raw version we’ve known until this point. In normal Zombie maps, you need to reach higher rounds to begin collecting them. Refined Crystals begin appearing at round 15, while Flawless will start to be gathered at round 20. If you exfiltrate, you have a chance to gain even more upon finishing the match, but you will also gain more of each crystal after every five rounds you survive.

Refined and Flawless Aetherium Crystals can also be obtained in Outbreak by completing multiple main objectives in a single match. Every time you start a game, you will have a random primary goal your squad needs to work towards together to pull off. When done, your team needs to decide if it is time to exfil or take an Aether portal to a different location and get a new main objective.

When going for Refined Crystals, they can begin appearing after completing two Outbreak levels but are more likely to not start until after three. The earliest we have seen Flawless Crystals appear is after four levels as of this writing. As you complete more objectives in a match, they will begin stacking on top of each other.

Screenshot by Gamepur

Once you gather up four Refined Aetherium Crystals, you can spend them on one level four upgrade of a skill that has been upgraded to level three. With five Flawless crystals, you can then upgrade that to level five. You cannot skip skill tiers, so you will need to plan out in which order you want to unlock these upgrades.

Outbreak is probably the fastest area to gain Refined and Flawless Aetherium Crystals, but regardless of where you prefer to play, just survive as long as possible into the game, and you will start gathering these rarer currencies.

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