Ether

The element of life. This is what a soul consists of.

The parts of the Worldplane where the Tree of Life's emanations of ether don't reach (due to the infinite geometry of the Worldplane) are presumably not inhabitable by intelligent beings (beasts do not possess a soul and therefore are not "alive" in the same sense humanoid races are).

The most versatile of the elements, abilities of its users range from healing powers to physical empowerment, sensing the presence of humanoid creatures, violent expulsion of ether energy, and in extreme cases even full control over any ether within a certain range, including any living creature's soul. A very high level user can effortlessly extinguish the life out of anyone in the vicinity in the blink of an eye, regardless of whether the victim is perceptible through conventional means.

Offensive ether blasts are notable for being more or less painless despite damaging the body. Ether energy can also have a beneficial effect, depending on both the user's intention and the way the energy is cast. This works similarly to how a caress and a slap both involve a very similar movement, but performed differently leading to an almost opposite effect.

Additionally, it's possible for advanced users to copy the shape and some of the effects of the other two elements. Examples of this are conjuring up green-hued ice that can be used to immobilize foes but that doesn't feel cold to the touch, or green flames that don't feel warm, and can either invigorate (lighter green) or damage (darker green) the recipient, depending on the user's intention.