Each time you hook a Survivor, Leverage activates and gains 1 Token, up to a maximum of 10 Tokens:

For each Token, the Altruistic and Personal Healing speeds of Survivors are reduced by a stack-able 3/4/5 percent for the next 30 seconds, up to a maximum of 30/40/50 percent.

At the start of the Trial, 4 random 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 effects apply:

The Generator with the most Progression explodes, instantly losing 9/12/15 percent of its Progression and starting to regress.
Survivors repairing that Generator will scream, but not reveal their location.

The Auras of Survivors attempting to blind you with a Flashlight are revealed to you for 6/8/10 seconds.
Lightborn grants immunity from being blinded by Flashlights, Firecrackers, Flashbangs, or Blast Mines.

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

The Auras of Scourge Hooks are revealed to you in white.
Each time a Survivor is unhooked from a Scourge Hook, the following effects apply:

The Auras of all other Survivors are revealed for 5/6/7 seconds.