Do you think this will do it? See pic

That will work as long as your activation circuit or trigger can only operate once during the time delay. According to the report a second push of the button will "immediately stop the delay".
So have you decided on what type of trigger you will use?
SG

 

That will work as long as your activation circuit or trigger can only operate once during the time delay. According to the report a second push of the button will "immediately stop the delay".
So have you decided on what type of trigger you will use?
SG

I’m thinking a micro switch linked to the coin drop on a charity box.

The idea is that a donation will welcome you to the Halloween party.
I have an old shed that will be blacked out on the inside.
Once activated a car windshield wiper motor will bring the grim reaper out/in sight with the smoke machine and strobe. All this coupled with a recording of screams and a warning message will hopefully have the desired reaction from my guests.
I am also working on a automated guillotine.

 

I’m thinking a micro switch linked to the coin drop on a charity box.

The idea is that a donation will welcome you to the Halloween party.
I have an old shed that will be blacked out on the inside.
Once activated a car windshield wiper motor will bring the grim reaper out/in sight with the smoke machine and strobe. All this coupled with a recording of screams and a warning message will hopefully have the desired reaction from my guests.
I am also working on a automated guillotine.

What I do need is something like “a perfect storm” box for lightning.