Putting a Survivor into the Dying State with your Basic Attack blocks their Aura from being revealed to any Survivor, who is farther than 32/24/16 metres away from them.

For the next 15 seconds, the following effects apply to the dying Survivor:

Reduces their Field of View and causes them to be deafened.
Suffers from the Blindness Status Effect.
Reduces the Crawling speed by -50 percent.
Reduces the Recovery speed by -25 percent.

After hooking a Survivor, THWACK! activates:

The next time you break a Breakable Wall or a Pallet, all Survivors within 28/30/32 meters of your location will scream and reveal their Aura for 4 seconds.

Destroy dropped pallets, breakable walls, and generators 20percent faster.

Any Survivor who blinds you or stuns you using a Pallet becomes the Obsession.
Anytime your Obsession switches to another Survivor by any means, that Survivor then suffers from the Oblivious Status Effect for 40/50/60 seconds and their Aura is revealed to you for 4 seconds.
You can only be obsessed with one Survivor at a time.

Each time a Survivor is hooked for the first time, you gain a token.  Upon reaching 4 tokens Grim Embrace activates.

The Entity blocks all generators for 40 seconds.  The Obsessions aura is revealed to you for 5 seconds.

Performing the Damage Generator Action on a Generator applies Overcharge:

The next Survivor interacting with that Generator is faced with a difficult Skill Check.
Failing the Skill Check results in an immediate Progression loss of 3/4/5 percent.
Succeeding the Skill Check grants no bonus Progression, but prevents the Generator from exploding.
After Overcharge is applied to a Generator, the following effect applies:

Increases the Regression speed from 75 percent to 200 percent over the next 30 seconds.