Some mobile games get coloring books, but not many have novels written about them.

The scarily successful Five Nights at Freddy’s horror series — available on iOS, Android, and PC — now has a tie-in novel, co-written by series creator Scott Cawthon and a professional writer going by the name Kira Breed-Wrisley (which sounds like a pen name, given this amateur sleuthing on Reddit). Five Nights at Freddy’s: The Silver Eyes is a 464-page take on the Freddy’s story, and it’s available on Amazon Kindle for $3. It’s also coming out in hardback in 2016, according to Cawthon.

The novel is set ten years after a series of murders at Freddy Fazbear’s Pizza, the home of four creepy adult-sized animatronic animals, when Charlie, the owner’s daughter comes back to town.

“Curiosity leads Charlie and her friends back to the old pizza place,” reads the blurb, “and they find it hidden and sealed, but still standing. They discover a way inside, but things are not as they once were: the four mascots that delighted and entertained them as children have changed. The animatronic animals have a dark secret and a murderous agenda.”

Cawthon was working at the discount store Dollar General when he found unexpected success with his first Five Nights at Freddy’s game last year. He’s gone on to create three sequels in quick succession, leading to some criticism and vitriol from gamers on forums and YouTube. Cawthon has responded with dignity and humility, though, saying, “It’s difficult when people seem to dislike you only because you’ve found success with something. I think some people have this idea that I spend my days swimming in gold coins like Scrooge McDuck and cranking out games with no effort — then laughing all the way to the bank. The reality is quite different, and I think that people who hate on me for being successful are misguided.”

“I worked as a cashier,” he said of his life in 2014. “I had three bosses who were all still in high school. Before that, I worked at Target in the backroom freezer, unloading frozen foods. I haven’t had a successful life; and now that god has blessed me with some success, I’m doing my best to be responsible with that success.”

Amazon users have responded well to the book, which released yesterday. It’s currently sitting on a rating of four-and-a-half stars, with 25 five-star reviews.

“An amazing book to help discover the lore inside,” reads one review. “I flew through it and was at the edge of my seat. Also, it was a great stress relief from the stress of college finals! Because everyone knows killer robots are the best to combat stress.”

Not everyone is so impressed, though. One reviewer says the series has already been milked to death and describes the book as a “cash-grab … with characters so flat that they are basically pita bread.”