My magic system involves groupings of elements called domains which have a unique property not specific to either element in said domain. As the title implies I'm looking for a element to be paired with light. So far I've been using "aether" as a kind of vaguely defined place holder as the second element in the grouping with it's definition being a strengthening lifeforce that can make things burn brighter or hotter as well as make an item more durable. At first I thought it worked since the opposite domain would be of darkness and void with void being an absence or negation of certain properties and aether being the enhancement of said properties. But I've started to reject that idea of aether because its definition encroaches on the unique property of the domain it's in, specialization. The ability to share Phantasia(the base energy of my magic system) with others to "specialize" in certain benefits. Often in the form of healing or support skills like buffing stats in a video game. I worried it made what would otherwise be a generic property for either element a specific definition for the one element.
With this in mind what's a good element to pair with light that fits the unique property I've established?
Also just so people don't suggest elements I've already put in other domains, the elements I already have are:
Fire and poison.
Animal life and plant life.
Earth and metal.
Water and ice.
Darkness and void.
Wind and electricity.
As can be seen with the grouping of fire and poison together, I don't need the element suggestions to match perfectly in substance with light. Just the overall theme of the domain and its unique property. In the case of fire and poison it's the ability to inflict lasting damage or status effects. While the domain light is in is a more supportive role as already mentioned but can still deal heavy damage if needed. As the energy shared will return multiplied exponentially.