The following packets are unused and have no reason to have handlers:
- CI: character information, unused and handled by SC.
- EI: evidence information, unused and handled by LE.
- EM: area and music information, handled by SM, and obsoleted by
dedicated FA and FM.
- MM: clientside toggle of whether a client is allowed to change music.
The handler doesn't even do anything beyond acknowledging its
existence.
- RMC: plays a music track with an offset. Unused in practice, not
present in AO2 Client.
- ackMS: sent by the server to acknowledge an IC message, a relic from
AO1.