Matrix is an open-source decentralized privacy oriented messaging platform on which allows people to have full control over their communication and privacy.
Matrix homeservers can be selfhosted on any computer using special Matrix server software. Drgnz is using Synapse.
You can use webclients hosted by Drgnz such as Element, Cinny, Hydrogen or SchildiChat.
You can install some clients on Linux such as Nheko, Element or Cinny. If you want something CLI, you can install Gomuks.
Currently Drgnz Matrix is invite only. You will need to reach out to the admins to get your account.
If you want to log into your account, you need to set your homeserver as m.drgnz.club! Just drgnz.club won't work!
Here are official Drgnz hosted rooms.