The Energy and Lightning Demons are some of the oldest known entities to have encountered mankind and were depicted on Paleolithic cave paintings. The earliest known cave painting of any kind was discovered in Europe and dates to 32,000 years ago. Based on the paintings, these demons bond with lightning to energize themselves then use their power to steal people's souls.  When an ice age came, there were no more lightning storms to draw strength from. The demons went underground and entered into a state of dormancy for several millennium. 
In 1997, the Energy Demons awakened and began drawing power, first from man made power sources. This resulted in a series of power outages throughout New York City. They first appeared near the New York Subway's 135th Street Subway Station. However, the Sub Dwellers (or Mole People as they are known in urban legend) were wrongly blamed for the incidents. The Extreme Ghostbusters agreed to help one of them, Persefineathious, and find the demons. They tracked the entities to a transformer terminal for the subway system. The Extreme Ghostbusters were unable to capture them, however, after they were met with electrical counterattacks.
A judge soon issued a warrant for the arrest for all Mole People. The police officers assigned to the arrest were also attacked by the demons. The Energy Demons then flew to the surface and appeared at Times Square. However, they were headed to a bigger source of power, the Empire State Building. The Extreme Ghostbusters quickly traveled to the building's observation deck and considered attacking with Proton Streams at maximum pulse. It was too late and they were completely energized by lightning. The Ghostbusters quickly adapted and blasted a lightning bolt before it hit the building spire. The demons were then infused with protons and trapped.
The Energy and Lightning Demons have the power to absorb electricity and emit blasts of electricity to defend itself. The more energy it absorbs, the larger in size and power the demon becomes. It is said when these demons bond with lightning, they can absorb human souls. The residue of these demons can cause vehicles to become animated.
Although not stated by anyone, on the Spengler's Spirit Guide Demon Browser, they are described as a Class 6 Floater. Egon Spengler does mention they belong to the wide field of Energy Sucking Demons or ESD's. 
Spengler's Spirit GuideEdit
- Level 6
- Wave Frequency
- Power Demon
- Class 6 Floater
- This demon should be avoided at all costs. It is ancient and highly intelligent.
- First Sighting
- Paleolithic Cave Paintings
- ↑ Official Extreme Ghostbusters Website Ghost Activity Archive Default page
- ↑ Egon Spengler (1997). Extreme Ghostbusters- Mole People (1997) (DVD ts. 10:01-10:02). Sony Pictures Home Entertainment. Egon says: "Power Demons."
- ↑ Egon Spengler (1997). Extreme Ghostbusters- Mole People (1997) (DVD ts. 10:03-10:11). Sony Pictures Home Entertainment. Egon says: "Sole documentation found in Paleolithic cave paintings. Said to bond with lightning to energize themselves and use their power to steal people's souls."
- ↑ Egon Spengler (1997). Extreme Ghostbusters- Mole People (1997) (DVD ts. 10:25-10:35). Sony Pictures Home Entertainment. Egon says: "I have a theory. The Ice Age arrived. No more lightning storms. Perhaps the demons went underground where they lay dormant for several millennia. Once they awoke..."
- ↑ Egon Spengler (1997). Extreme Ghostbusters- Mole People (1997) (DVD ts. 02:05-02:14). Sony Pictures Home Entertainment. Egon says: "Energy sucking demons or ESD's. It's quite a field of this type of entity but based upon your description, we should be able to narrow it down."