You become obsessed with one Survivor.  When the Obsession loses a health state, your Terror Radius transfers to the Obsession for 30 seconds, and its radius is set to 32 meters.

You are granted the Undetectable status effect for the duration.

The Survivor with the transferred Terror Radius is also considered to be "inside the Terror Radius" for other purposes.

The Killer can only be obsessed with one Survivor at a time.  Undetectable hides the Killers aura, Terror Radius, and Red Stain.

When you put a Survivor into the Dying State with your Basic Attack, all Generators within 32 metres of you instantly explode and start regressing.

Applies an immediate Progression penalty of 6/7/8 percent.

If there is at least one Dull Totem remaining in the Trial Grounds, Hex: Plaything activates on a random Totem each time a Survivor is hooked for the first time:

The hooked Survivor suffers from the Cursed and Oblivious Status Effects until Hex: Plaything is cleansed.
For the first 90 seconds, only the Cursed Survivor is able to cleanse the Hex Totem.
The Aura of Hex: Playthings Hex Totem is revealed to the Cursed Survivor within 24/20/16 meters.
The Hex effects persist until its Hex Totem is cleansed.

Each injured, dying, or hooked Survivor afflicts Survivors with a stack-able 1/1.5/2 percent Action Speed penalty to Repairing, Sabotaging, and Cleansing, up to a maximum of 4/6/8 percent.
Increases the Action Speed penalty by a further 12 percent, if there are 4 Survivors, who are either injured, dying, or hooked at the same time.

Gain a notification when a Survivor begins sabotaging a hook.

While carrying a Survivor, see the aura of any survivor within 6 meters of a hook.

The Auras of Breakable Walls, Pallets, and Windows are revealed to you within 24/28/32 meters.