1. Obtain points : We need to obtain points by completing tasks. The location of the mission can be found from the question mark on the map.
2. Complete tasks : After completing these tasks marked with question marks, we can get a certain number of points.
3. Use points : Points can be used to open the door in front of the BOSS in the Goat Tower. Each door opened will unlock a new open area.
4. Challenge the BOSS : After opening the door, you can start fighting the BOSS.
This is the guide on how to open the boss door in Goat Simulator 3. I hope it will be helpful to you.