Hey, I think it would be cool to have a RMX-OS add on where two guilds fight each other. Things it would be able to do:
1. Chat command for "challenging" another guild.
2. Can configure kill limits for guild battles.
3. Can configure what happens upon challeng (transfered to another map, etc.)
4. Can configure a special respawn point for players killed in guild battles.
That's all

! The scripts I'd be using with it:
Default RMXP scripts, RMX-OS, Blizz-ABS (and its RMX-OS plugin).