Along with diving, controllable airships, and delicious lattes, a whole combination of two special elements inherent to the residents of Fontaine has emerged - Pneumosia, or Pneuma, and Ousia, separately. In this guide, we will find out what they are, why they are needed, and how to use them.

Also, to prevent confusion in terminology, Pneumosia can refer to both the interaction process between Ousia and Pneuma and their combination, generalization.

Bearers of Pneuma and Ousia in Genshin Impact

As I mentioned earlier, the residents of Fontaine are the bearers of these, both Pneuma and Ousia, except for the Hydro Traveler. It's very easy to distinguish between them by looking at the symbols on the Eye of God. Pneuma's symbol is geometric, diamond-shaped; Ousia's is circular.

Energy is released with specific attacks. The list of characters and skills that trigger each type of energy:

• Hydro Traveler, Pneuma (elemental skill).
• Lyney, Pneuma (charged attack).
• Lynnette, Ousia (elemental skill).
• Freminet, Pneuma (elemental skill).
• Neuvilette, Pneuma (elemental skill).
• Wriothesley, Ousia (elemental burst).
• Chlorinda and Navia possess Ousia, while Charlotte possesses Pneuma.
• Attachment to skills at the time of writing the guide is unknown.

This action looks approximately like this:

NB: Pneuma - light, Ousia - dark. 

Working Principle of Pneumosia in Genshin Impact 

Your gameplay in solving puzzles will revolve around influencing one on the other and vice versa. Some core enemies of Fontaine (such as Abyss Herald or Icewind Suite) are charged with one of these energies. You can identify this factor by observing the glowing effect.

Applying the opposite energy (Pneuma on an Ousia-empowered enemy or vice versa) puts the enemy in a weakened state (often paralysis). The same principle applies to puzzles: apply the opposite energy. To avoid fruitless frustrations, remember that there is an internal cooldown for applying Pneumosia, so you can't spam it in combat or puzzle-solving. 

Pneumosia in the World of Genshin Impact 

During exploration, in addition to the affected mobs, you will often encounter:

• Pneumosia Blocks. They save you from the painfully frequent switching of squads and adding a user with the corresponding element. They do it all for you - you pick, hit someone/something, and leave happy with a defeated enemy/treasure chest behind.

• Transmission Pillars - a popular puzzle. It's similar to torches but follows a general rule. 

• Boxes. Usually contain Blocks, but sometimes there are treasure chests (it's a matter of pure luck and having an interactive map at hand).   

• Amplifiers. They buff enemies within their radius. Similar to the mentioned actions, they are deactivated by the opposite energy applied. 

• Airships. Flying machines operate on Pneumosia propulsion. 

That's all. I hope the explanation turned out to be clear! Many thanks to TevyatTimes and CatWithBlueHat for the screenshots.