The syn IRC network runs on ngIRCd with some minor code changes. It is different from other networks in many ways, some notable things you can expect from the network are:
The goal is to create a network where privacy and anonymity are an expectation, and censorship, tracking, or other forms of user discrimination are impossible. It is primarily encouraged to use hidden services to connect to the network. There is currently one server that supports Tor/I2P:
syn [6667]irc.i2p [355jdcopct34lpun3o6cfiymcmsoto3wic4ueu63wxwqlm2bpioa.b32.i2p]
synripul4ztvmpv6avnjkvozshprdcncb2ikz3n74iubay3ayidbi2qd.onion
synnn3y657fyqo6e6v4tkxhpks3ftm4qqjc6hqnowv2l6z7cqls5ftad.onion
If you are interested in linking your own server, message any user logged in as an operator, on any currently linked server for further information.