The controversial McKamey Manor in Summertown, Tennessee – once described by its owner as a “survival horror boot camp” – is offering $20,000 to anyone brave enough to survive its new horror experience.

Russ McKamey has long fielded concerns over the safety of the attraction.

In an interview with The Guardian in 2015, McKamey admitted that a visitor once had a heart attack.

Accounts from those who have attempted the tour have also detailed the horrific experience the Manor has in store.

A visitor named Amy Milligan told the San Diego Union-Tribune in 2015 that she was slapped and waterboarded at its former location in San Diego - and in a reader poll, 70% of people said they thought the experience was "too extreme."

Meanwhile, visitor Laura Hertz Brotherton told Nashville Scene: "I still have scars of everything they did to me. I was repeatedly hit in my face, over and over and over again. Like, open-handed, as hard as a man could hit a woman in her face."

She added that she was forced, like all other visitors, to film an "exit video" before she could quit, and that McKamey told her he would sue her if she didn't say good things about the Manor.

Despite all of this, McKamey is still encouraging thrill-seekers to join the thousands-long waiting list - and is even offering a financial reward.

A video released on Tuesday announcing the attraction's "Desolation" tour promises "a new level of extreme horror" to those with the guts to sign up.

Warning: Even the video isn't for the faint-hearted.

McKamey told Insider he was offering $20,000 to whoever makes it all the way through the new tour, but he warned that nobody ever has.

Visitors must sign a 40-page waiver

All visitors must meet the manor's entrance requirements: They must be "physically and mentally cleared" by a doctor, pass a background check, and sign a detailed 40-page waiver.

The entire experience is also filmed by McKamey, who told WFLA this week that "nobody's even made it to the starting clock with this new show."

"With the new mental game, it's much more difficult," he said.

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A nearly two-hour video posted on the manor's YouTube channel in August says it shows "every contestant who has ever attempted" the tour since July 2017.

"Legally, anyone desiring to participate in the MM experience called 'DESOLATION,' must watch this entire movie for their safety," the video's description says.

The tour is free- McKamey offers only dog food as payment - but the manor offers a stark warning to all would-be visitors: "Each tour will be different based upon your personal fears, and can last up to 10 HOURS. Each guest will be mentally and physically challenged until you reach your personal breaking point." It adds that "you will be tested to your very core."

McKamey and his home have garnered national and international attention over the years. McKamey Manor has been described as one of America's scariest houses, with The Sun, The Guardian, and Ladbible all reporting on the terrifying experiences on offer.

Nashville Scene gave an in-depth report of what a visit to the Manor is like, calling it "torture on demand."

The Manor previously existed in San Diego, but McKamey was forced to move.

However, Lawrence County Commissioner Scott Franks told the Scene of its new location: "It's legal because basically the people that are subjecting themselves to the McKamey program, or whatever you want to call it, they're doing so voluntarily."

McKamey Manor appeared on "Haunters: The Art of the Scare," a 2017 Netflix documentary about a new breed of horror attractions that's "not going to scare you - it's going to scar you."

The manor was also featured on episode eight of "Dark Tourist," in which the presenter David Farrier quit long before the real horror experience even began.