The symbols surround a pentagram at the center. Use the ring on the pentagram and the symbols similar and those seen beside the bodies of the 5 mortals killed light up. Click the red jewel beside the symbols in the order seen throughout the game.  The door will slide open when done correctly.

pentagram puzzle 1Pentagram Puzzlepentagram puzzle 2Use the ring on the pentagrampentagram puzzle 6Pentagram Puzzle complete