You drink healing water and restore HP, you approach the obelisk, and ghosts-mages appear around you; get away! They shoot at you, dealing -45 HP damage; you need to do something urgently, for example, read the obelisk and run away, or call the necromancer passing by.
I quickly run away and drink Water from the Oasis (restoring HP), and then I run towards the obelisk like crazy, dodging the ghosts, and manage to read the symbols.