The ability to cause heads in the immediate vicinity to explode. This includes one's own head.
In Jhonen Vasquez's comic, Johnny the Homicidal Maniac, the main character 'Nny visits Heaven, having beeen denied entry into Hell. While in Heaven, 'Nny learns that, like all behind the pearly gates, the ability to explode people's heads has been conferred upon him. Very messy antics ensue, preceeded by an exclamation and a blood-thirsty grin, "I have Head Explody?!"
Exploding Head Syndrome, Aka EHS, is the felling you get, especially females, when you almost drifted to sleep, and you hear a loud sound like an explosion, fireworks, or even a gunshot. The victim then wakes up with no explanation.
A common sensation where one perceives the sound of an explosion, the feeling of a brick hitting their face, or another abrupt sensory impulse that jolts them awake, only to realize they were imagining it. This typically occurs as one is about to fall asleep, when one begins to dream before their body can enter a state of nocturnal atonia.
1: "...gah!!"
2: "Holy shit...! You good, babe?"
1: "Ah... yeah, I'm fine. Just an instance of exploding head syndrome."
2: "Well, good thing your head didn't actually explode, eh?"
1: "Heh... definitely."
The sensation of hearing a very loud noise in the middle of the night, typically when half-conscious. However the sound never actually happened. Sounds range from explosions and gunshots to even human noises. Rarely, there is a visual phenomenon accompanying the noise, such as a flash of light. The exact cause of the syndrome is unknown.