Create a new world in Minecraft Java Edition
Set the game mode to Hardcore
Enable multiplayer by opening the world to LAN
Make sure both players are on the same local network
Have the host player open the world to LAN from the pause menu
Note the port number shown after opening to LAN
The second player joins using Multiplayer
Select Direct Connect or Add Server
Enter the host player’s local IP address and LAN port
Start with shared survival goals and coordinate roles
Keep both players together or communicate constantly
Avoid unnecessary risks since death is permanent in Hardcore
If one player dies, the world is effectively over for both players
Use beds, food, armor, and shields as early as possible
Make backups only if you want to preserve the world outside normal Hardcore rules