Throughout the game there are locked doors that require keys to enter. Behind each door is a rare item. It can be kind of difficult to locate each door and it's corresponding keys, so I've made a table of them all here.
| Segment Address | Door Location | Decoder Location | Item |
| 1 | |||
| 2 | |||
| 3 | |||
| 4 | Pleroma Part I | Pleroma Part II | Thief Ring |
| 5 | |||
| 6 | |||
| 7 | Woglinde Part I | Woglinde Part II | Robot Part Right Arm |
| 8 | Elsa Part I | ||
| 9 | |||
| 10 | KOS-MOS Simulator Part II | Elsa Part I | |
| 11 | Pleroma Part 1 | ||
| 12 | |||
| 13 | |||
| 14 | Elsa Part I | ||
| 15 | |||
| 16 | Woglinde Part II | ||
| 17 | |||
| 18 | Woglinde Part I | Woglinde Part II | Coat-Lightning |