Running Minicraft on Debian-based Distros (Screenshots are Ubuntu 17.04)

  1. Open Terminal
    Terminal
  2. Do the command sudo add-apt-repository ppa:webupd8team/java
    Repository
  3. Do the command sudo apt-get update
    Update
  4. Do the command sudo apt-get install oracle-java8-installer
    Installer
  5. Download either Minicraft+ or Minicraft Deluxe from the previous page.
    Download
  6. Double click to play!

If the above does not work, you can try opening through the Terminal

  1. Open up Terminal
    Terminal
  2. Do the command cd (File Location)
    Changing Directory
  3. Do the command java -jar FileName.jar
    Opening

It's good to note that usally an error can be fixed with a restart or simply reinstalling Java.
If you are stumped or something didn't work, try asking the Discord here.