This is a modded Java server called Ash and Ale and it runs on version 1.20.1. They use their own custom modpack just for this server.
The whole thing is themed around medieval and magical stuff. It feels like a fantasy world with castles and spells and the players are the ones who shape the history.
The modpack is shared in their community so you join up and then jump into this world full of ash and ale and stories that players make together.
