A Worthy Mori (Shadowed Mori)
The Entity is not impressed with Killers spoiling all the pleasure by rushing to kill Survivors with their own hands too early in the trial and will now only grant the ability after a Survivor has reached struggle phase on the hook.
Once a Survivor reaches struggle phase the Mori offering becomes active affecting that Survivor with the Shadowed status effect and granting the Killer the ability to kill them with their own hands.
Survivors affected with the Shadowed status effect will have their aura and health status hidden from all other Survivors.
The last Survivor alive will automatically suffer from the Shadowed status effect and be able to be killed. (Much like how hook phase is skipped when you're the last Survivor)
When the killing (Mori) animation finishes it will act as a Sacrifice hook granting all the benefits of a hook.
Think of it as a mobile hook. (e.g., BBQ aura's are shown if they are not nearby, gives kill+hook points)
Killing (Mori) animation can no longer be cancelled or stopped.
In-game the Shadowed status effect could just be a big shadow underneath the Survivor or simply it could make their own shadow noticeably larger. It could be as though The Entity is watching the Survivor closely awaiting to enjoy the killing.
I think this makes the Mori offering fun and fair while still being scary. It could still be powerful in longer matches where multiple Survivors are on their death hook.

Comments
that's a pretty cool idea!!
Well, moris are not really a problem those days since you can see mori = DC lol
I like the idea, but I feel like the reverse aura blindness might be a bit too powerful. But it fits the theme, so sure why not :)
Could be made into a Hex perk, too