Fortress Gamemode
When Fortress Gamemode is active, the camera rotation angle is controlled by the game, and the mouse pointer is released.
X camera rotation depends on the height of your current position above the ground: when you are on the ground, the X rotation is 0, when you are 30 blocks above the ground, the X rotation is 90 degrees.
The released mouse pointer can be used to select blocks to build and destroy. Left-click is used to select areas to destroy, right-click is used to select areas to build.
When a world is generated, you spawn with the three pawns around you. You immediately can fly above the ground and give instructions to your pawns.
Known issues:
Sometimes, after the world creation, the camera is stuck with a zero X Rotation angle. To solve the issue, exit the world and then join it again. The camera will start to behave normally.