After a generator is repaired, The Entity blocked the generator with the most progress for 30 seconds.  You see its white aura during this time.

Once the Exit Gates are powered, if there is still a Dull Totem remaining on the Map, Hex: No One Escapes Death activates and lights it:

Increases your Movement speed by 2/3/4 percent.
Survivors suffer from a permanent Exposed Status Effect.
Hex: No One Escapes Death remains inactive if no Dull Totems are available.

Once the Status Effect is revealed to Survivors, Hex: No One Escapes Death reveals the Aura of its Hex Totem to all Survivors within 4 meters and gradually expands that range to 24 meters over the course of 30 seconds.

The Hex effects persist until its Hex Totem is cleansed.

At the start of the Trial, 4 random Hooks, as well as the Basement Hooks, are changed into Scourge Hooks:

The Auras of Scourge Hooks are revealed to you in white.
Each time a Survivor is hooked on a Scourge Hook, the following effect applies whenever you are farther than 24 metres from the hooked Survivor:
Accelerates the Sacrifice Process by 10/15/20 percent.

Whenever a Generator is repaired to 90 percent, Survivors repairing it are faced with continuous Skill Checks.
If they miss one or stop repairing, the Generator becomes blocked for 16/18/20 seconds.
Merciless Storm can only trigger once per Generator per Trial.