The Nightmares made a humming noise in satisfaction of their latest meal. The poor thing even struggled and put up a fight, something the Nightmares relished seeing as their current host didn't fight at all. He thought he was in control.
The Nightmare Man he may be known to others, but he was in, all reality, the Nightmare's man.
The Nightmares swam around lazily in the liquid while they translated a signal from one of their spies in the Abarat world. They zapped through information quickly but it only came down to one line of the message.
Everything is ready
The Nightmares hummed slightly louder in excitement after years of planning and sabotage, their plans were going to come to fruit. The nightmare wiggled lower nearing the base of the skull of the mortal. They easily sent out zaps of electricity, already sure that the neurons would send the impulses to the correct receptors in the brain that would cause the chemical imbalances needed for their plans to work.
Once they were done, they went about wiggling in their temporary home and waited for the Nightmare's man to fall into a coma like state.
And then, they would take over.