As some players choose to play with an iMac, Macbook Pro or Macbook Air, there will occur complications as Java and iOS don't exactly go hand in hand.
Frequent issues & Fixes:
Black Screen
Holding down the "S" button whilst loading the client should force the client into Software Mode and thus fixing this issue, as Mac does not support OpenGL or DirectX.
Can't Open the Jar
If you can't open the jar because it's from an unverified supplier, the way to fix this is by simply archiving the file. This is done by right-clicking the Exora.Jar and choose to Open-With the "Archive Utility". This will then create a compressed file in which you can later delete, but it'll allow you to normally open the Exora client normally afterwards.
Java Versions
You're always going to want to have the latest version of Java installed on your Mac in order to maximize the performance of the client.
Standard Java for MacOS
Alternative Java for MacOS
If none of these help then be sure to request help by sending a Staff Member a Private Message either on the Discord, Forums or In-game.