Mining the precious coins is no easy task and each Cyber can endure only a certain amount of mining sessions. Each mining session, either it's won or lost, will result in your Cybers sustaining permanent damage.
Each mining session will reduce the total cyber power of the Cyber usually by 1.5%. The damage percentage may be adjusted slightly based on the Omni-Balanced Oracle™.
The more mining sessions done by your Cybers over time, the weaker they will become, until their Cyber Power (= CP) reaches below 2000. Once a Cyber's CP is below 2000, then you can mark the 'hide weak Cybers' checkbox to hide them from your inventory. The only way to replenish your Cybers will be by adding more Devs and Servers. However, keep in mind that you can only add more Devs and Servers until you reach 10 Servers per Cyber, and taking into account the maximum number of Devs that each Cyber can support.
If you don’t mine with your Cyber, then it’s total Cyber Power will not be reduced.
Once a Cyber is formed, it cannot be dismantled. It is not possible to remove Devs/Servers from a Cyber once they are inside it. The Cyber can only be executed as a whole. You can also choose to sell your Cyber in the marketplace.