Fly with nostalgia
Fly with nostalgia is a mod adding a retro flight mode, similar to the pre-creative days of Minecraft. Players with the retro flight mode active can walk through the air on glass platforms which slowly disappear behind them.
Note: The plugin currently uses a Mixin to register a world tick listener. That is planned to be replaced with Sponge API in future releases.

Commands
/fly
Enables or disables retro flight mode for the player. All the arguments are optional.
Command format: /fly <targets> <radius> <enable>
targets - choose one or more players for whom the retro flight mode will be toggled.
radius - set how big the platform should be (in blocks around the player). Defaults to 3.
enable - specify if the flight should be enabled (true) or disabled (false).