Deep Dungeon: Madou Senki/Floor 7

Key Points

 * 1) You will find the crown that allows you to speak safely with the princess at (22, 13).
 * 2) There is fake Princess Etna at (22, 19) who will force you into a fight.
 * 3) The real princess is located at (29, 7), but you must possess the crown first.
 * 4) You will always encounter a Shadow Knight at (29, 27).
 * 5) There is a Stone Statue garding a door at (15, 14).
 * 6) Beyond that door, you will find the Mark Ring by searching the ground at (17, 15).