Simple: its the same cubecraft server but with everything unlocked. Of course, there will be a price. (e.g. only ranked members get access.) This is purely for testing, not playing. Anything that has been done there will not affect the normal server. This way, instead of staffs players can report bugs and glitches. To stop people making this the main server, the profile will reset every time you get out of the server.
(PTS stands for Public Testing Server)
(PTS stands for Public Testing Server)