Halloween 2017 Event Re-Run/Free Quest/Inverted Pyramid

Burial Chamber
Clear Mission No. 43 to unlock

Prayer Room
Complete Mission No. 28 to unlock

Ventilation Orifice
Clear Mission No. 66 to unlock

Great Stairs
Clear Mission No. 95 to unlock

Great Hallway
Clear Mission No. 76 to unlock

Concealed Passageway
Clear Mission No. 53 to unlock