VoidNetwork is a new server that just launched after weeks of building and it is focused on a fully custom prison experience.
The prison release brings private mines with custom skins plus custom enchants. There is also an auctionhouse so players can trade and sell stuff. If you like risky fun you can coinflip against other players.
It also has lootboxes that are packed with rewards and more features beyond that. The server says they are also working on a brand new original gamemode called Chunked and they share more info in their Discord.
Forsaken Realm Mod Test Server
This is a Java modded server for players 16 and up. It is built around a custom mod called Descent into the Realm Forsaken that the owner is making for 1.21.8.
Right now the server is mainly for testing before the next big update. People play to try new stuff and help spot issues while things get added.
If you want a fun place where changes happen during the season and everyone is cool with testing then this one fits.
GG.MINEWIND.NET New Server IP