Officially this game tested/supported on Ubuntu.
You are using Mint.
Possible causes of the problem in the following libraries: QT, SSL (OpenSSL or other), etc.
The post was edited 2 times, last by vpchelko ().
The most common issue with failed certificates is a wrong system time.
sudo apt-get install ntpdate
and certificate authority package
sudo apt-get update
sudo apt-get install ca-certificates
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