Minecraft Hardcore Servers
Hardcore servers are the multiplayer version of hardcore mode from singleplayer Minecraft. The key rule is players only get one life, and death results in a ban from the server. The length of the death ban varies from server to server, and could be anything from 15 minutes all the way up to hours or even days. On the most extreme hardcore servers the ban is permanent - if you die you're banned for good and can never play again.
These servers are set to Minecraft's hardest difficulty level, meaning mobs deal more damage, hunger is more dangerous and survival is significantly more challenging. And it's not just the environment you need to worry about. Hardcore servers usually have PvP enabled everywhere and allow griefing and raiding. All things considered, joining a hardcore server is one of the most intense and unforgiving ways to play Minecraft, and is definitely not recommended for beginners!