MCCP (Mud Client Compression Protocol)
MCCP is a protocol for sending compressed data from the server to the client. It can greatly reduce the outgoing bandwidth from the mud, and may also decrease client latency. You can read more about it here.
Of the 275 active characters on God Wars II, 230 use MCCP, and of those only 78 last connected from a unique IP address. Of those 78, 4 refused to identify their client. The remaining 74 characters are broken down by client as follows: