RF Online
A sci-fi MMO where three races fight over one mine: Bellato mechs, Cora magic and Accretia gunmetal. Each episode is its own server and its own client.
Versions
Each one is its own server against its own game client. They are not upgrades of each other: pick the client you have, or the one you want to play.
The last Taiwan build of the 4.x line: a far bigger store, eleven more maps, and item collections.
Four new maps, the High Gold MAU, and a level 80 cap.
Episode 2.2.3.2, the one most people mean by RF Online. Gold Points, three battle dungeons and the Bio Lab second basement, at a level 65 cap.
Episode 2.1.6. Red Army plus the Holystone line: Blue MAU and Blue Siege Kit, Kartella Bio Lab, PvP points, and Superior armour built through Crystal Talic.
Episode 2.1.5. Beast Mountain and Outcast Land open up, the Archon gets real power over a race, and the Red MAU and Siege Kit arrive at the level 55 cap.
The last version of RF Online before the cash shop. Three races at war over one mine: Bellato mechs, Cora magic and Accretia gunmetal.
Not an episode but a reworking: a 2011 relaunch that rebuilt the interface and added systems the other versions never had, under a version number that went down while the game went forward. It was shut down, and it is the one RF here almost nobody played. The client it speaks to is the GamesCampus 1.5b build.
What they share
Documentation that is true for every version in this family.