Made this base on an old smp world I made with a few friends. There was a lot more to it but it was lost in a save mixup.

The entrance is hidden with a small cobblestone generator and protected by a bedrock shell and a basic 7 digit combo lock with a lava trap that activates on one wrong key entry. This base was meant to be used with the Blift bukkit mod since I used that for elevators back then but it can easily be replaced. There's a shaft that goes down to bedrock where there's a vault and a lot of building potential.

After I made the schematic and checked the base I noticed a problem with the door the combo lock opens and some missing blocks in the vault, just a heads up.