Protodisk is one of the rarest and most valuable resources in Arknights Endfield, not only because it’s used to promote every single character on the roster past level 20, but because it’s farmed from combat events rather than gathered from the open world.
So you can raise your Operators to the next level, here’s how to secure a steady supply of Protodisk in Arknights Endfield.
Where to get Protodisk in Arknights Endfield
Unlike similar resources such as Pink Bolete or Kalkonyx, the best source of Protodisk is by completing “Protocol Space: Promotions” combat events.
Alternatively, you can also get Protodisk by using these Arknights Endfield codes distributed by Gryphline, the game’s developers.
Protocol Spaces are repeatable combat trials with different difficulty levels which dish out fixed rewards for completing them. The challenges themselves often come with an extra difficulty modifier, such as SP recovery being reduced or some other hurdle.
However, an extra wrinkle is that there are many different types of Protocol Spaces. To get Protodisk for promoting characters, you need to look for the “Promotions” ones specifically.
Other Protocol Spaces, such as “Weapon Tune” or “Skill Up”, all give different kinds of rare resources, so you need to make sure you’re doing the right kind of challenge before you start.
To attempt a Protocol Space, approach the rift, which looks like a black tear in the fabric of reality. Here you can choose the level of challenge you want to take on, as well as review the fixed rewards.
You will then be teleported to the combat arena, then, once you’re hopefully successful, you’ll be taken back to where you were with more Protodisk in your pocket!
Protocol Spaces are limited events, meaning you need to consume “Sanity” to claim the rewards from them. This means you can only complete as many in one day as you have Sanity to spare, but you can always use the Sanity recover items you receive from upgrading your Authority level to complete more.
For more on which characters to promote with your Protodisks, here’s our Arknights Endfield tier list.