Witchaven/Level 22

From the start, go through the door, turn right and drop down, then jump up the small elevation and follow the curved brown hallway. When you get to the spot where arrow traps fire from the walls and a Skeletal Witch attacks, you will find a translucent illusionary wall to your left, where you will find the pentagram.

Continue following the corridor, and when you reach the dropoff, take it, jumping up onto the grass and then the continuation of the brown stones to keep following their path. Head up the curved stairway to your right and open the door that you see across the way at the top to find the black key.

Head back downstairs and go across the uneven tan rocks in the middle outdoor area, finding yourself back at the start. Head up the short flight of steps and to the right, cross the bridge you come to, and turn right. The door to the exit (black key lock) is at the end of this hall, with another Skeletal Witch guarding the exit pad.

Bonus Areas

 * If you turn around from the start position, you'll find a glass skull right nearby.