Yedang Online announced they changed their Massive Multiplayer Online (MMO) 3D Space Shooter game's title from Flysis to AirRivals. Players have to un-install the old Flysis client and install the new AirRival client. But the accounts and data are still available.

FLYSIS is an action based Massive Multiplayer Online (MMO) 3D Space Shooter.
In Flysis players can pilot their own fighter ships (Gears) on an imaginary planet and upgrade skills or the Gear itself.
In Flysis gamers have full control over the Gear's movement, making it very different from the traditional RPG's mouse click control method. This is a game based on Role-Playing Game (RPG) level concepts, but the fun and action of a First Person Shooter (FPS).

Announcement from http://www.airrivals.net/

Change of game title - 2008/03/06
Due to copyright issues we were forced to change the title of the game. If you are new to the game, just create an account and then download and install the AirRivals clinet from here.
However, if you have installed the version with the old name, it is mandatory to:

1. UN-INSTALL THE EXISTING CLIENT
2. DOWNLOAD AND THEN INSTALL THE NEW AIRRIVAL CLIENT
3. YOU WILL STILL HAVE YOUR EXISTING ACCOUNTS / GEARS

Please be aware that there will be a character wipe (not an account wipe) at the end of the closed beta test (CBT). After CBT no further character wipe is planned.
Please also be aware that old accounts (before 2008/02/12) need to accept the Terms & Conditions by logging in the website (if not already done).