You are looking for "Death Dream", a 1988 novel by Graham Masterton. This novel is the second volume in Masterton's Night Warrior series, which starts with "Night Warriors". The series continues after "Death Dream" with "Night Plague", "Night Wars", and "The Ninth Nightmare". In the plot of "Death Dream", Masterton's night warriors come to the aid of a young boy who plays unwilling host to the prehistoric imagination monster. The creature projects itself from its host's dreams to tear its victims apart with its scythe-like claws.

You are looking for Death Dream, a 1988 novel by Graham Masterton. This novel is the second volume in Masterton's "Night Warrior" series, which starts with Night Warriors. The series continues after Death Dream with Night Plague, Night Wars, and The Ninth Nightmare. In the plot of Death Dream, Masterton's night warriors come to the aid of a young boy who plays unwilling host to the prehistoric imagination monster. The creature projects itself from its host's dreams to tear its victims apart with its scythe-like claws.