| Category | voidship life support/movement |
| Type | organism |
| Native | Void |
| Cost | 250,000 GP |
Void essences are organisms home to the Void. A skyship is classed a voidship if it has a void essence. In a symbiotic relationship, these organisms can maintain a livable atmosphere for those on ships traveling beyond a world's atmosphere.
Void essences are hard to find and even harder to keep alive when taken out of their natural environment. The rarity of them is why voidships are so expensive. The number of void essences required for a ship is based on its size, the rule of thumb is one void essence per 500 tons of ship weight (a ship of the line, mostly wood, averages 1,000 to 1,500 tons). One void essence can maintain a livable atmosphere for 50 medium-sized humanoids.
When taken out of their natural living environment, void essences are kept in an air-less encasing. This is required because these creatures feed on traces of oxygen while in their natural habitat. If taken and exposed to an oxygen rich environment, they overeat, explode, and die. These explosions can be deadly and violently destructive to the area around it, so much so that a lot of shielding is used to protect them. This protection cannot be too enclosing though, because they still need to eat. They eat more when used to provide a ship with its void movement and the atmosphere for the ship around them. It is not completely understood how they can provide oxygen for the ship around them, and not in turn be killed by it. One theory is that the carbon monoxide released from living creature's breath has something to do with this, in that void essences switch their food source to something they prefer even more than oxygen.