You will begin in a forest with an orange haze, as you progress you will enter a grove area and there will be two necromancers, deal with them and continue walking, you will come across a cave entrance. Once in the cave it'll lead to a fort, with the first room in the fort having two ghosts.
The first room of the fort also contains a secret area, with the lever being directly in front of you as you enter the first room, in this secret area is a boss ghost, once you have dealt with it, claim the silver chest and food surrounding it.
Once you are done with this first room and secret area, continue onwards and you will enter a small room with a ghost and a necromancer in it. After they are dealt with the next room will also have a ghost in it, the room after is the site of a where the necromancers attempted to harness the portal's dark power, surrounded by the skulls of animals, and a sacrifice in the middle. Once you are done in this room, head down the stairs and you will have to deal with three necromancers and two ghosts. There are two paths out of this room, take the one to the right to get to the final secret area, the room will have two necromancers to deal with, the lever is on the left and once activated will open a secret door behind you, this secret room contains a necromancer boss and a silver chest.
The next room is the final room and contains the final boss, who is a mercenary, it also has a ghost and necromancer patrolling.