I found a new SMP server called Extreme SMP and it is made to be very hard. It is not meant for casual survival and it feels like a real challenge the whole time.
The server has a hardcore economy and the players are competitive so you should expect people to play seriously. Progression is tough and you are supposed to earn everything the hard way.
It runs on version 1.21 and it is for people who only want to join if they can survive.
EXTREME HARD SMP CHALLENGE 1.21
bring your bestgrindy progression pathhardcore minded playersno handholding survivalprogression feels brutal
GG.MINEWIND.NET New Server IPBrand New No Rules Anarchy
This is a brand new Minecraft anarchy server.
There are no rules and it is all about chaos. You just join and see how long you can survive. Nobody will protect you and you have to watch your back.
If you like wild and crazy servers where anything can happen this one is exactly that.GG.MINEWIND.NET New Server IP