The magic spell is used in nearly all the books from the Living Dummy saga, and it also appears in the Give Yourself Goosebumps book, Escape from the Carnival of Horrors, and the film Goosebumps 2: Haunted Halloween.
The phrase is written on a card usually kept in the dummy's front pocket. Once the words are read aloud, the dummy comes to life. If the words are read aloud again, he goes back to sleep. In the television adaptation Night of the Living Dummy II, Slappy explains that the phrase means "you and I are one now." However, in The Ghost of Slappy, Slappy claims he doesn't know what the words actually mean. He thinks they might translate to "Slappy is awesome".
- In Slappy New Year! a message reading, "Hello. My name is Slappy. I can be your friend. Just read these words aloud, and I will come to life. We can have a lot of fun together.", appears on the card above the "Karru Marri..." phrase.
- While this message does not appear in any other piece of Goosebumps media, a shortened version appears in Haunted Halloween: "My name is Slappy. What's yours?".
- In Haunted Halloween, it was revealed that this spell could also bring other objects to life, not only dummies. However, this spell only works if it's said by Slappy.
- In Slappy's Nightmare, Jimmy O'James obtains a similar spell to use on Slappy, which when read aloud would bring a different dummy to life and put Slappy to sleep forever. In the book, Jimmy does not finish reading the curse, but he does read the first part of it which reads: "Kallah Meeha Arumah Kalumah Noba Reemuh Maru Odoni Mallah". The spell was cut off there as Slappy stopped Jimmy from reading any further.
- It was also revealed in Haunted Halloween that if Slappy reads the spell backwards (i.e. "Onarrak Unolom Amol Annodo Irram Urrak"), it would work in reverse and turn things that were alive into inanimate objects such as dummies.
- Slappy's eyes turn white when he reads the spell backward.
- In The Dummy Meets the Mummy!, there's also another phrase that can awaken a mummy named Arragotus.
- These words are never mentioned in I Am Slappy's Evil Twin, seeing as Slappy and Snappy are both alive already at the start.