I can suspend disbelief a bit. The Elements of EtG are primal cosmic forces and the periodic table is a manifestation of its complexity.
Still, Wood is a Compound of
, and Metal is a Subset of
these are pseudo-elements. I think combining them, into a 14th element needs a premise that unifies them.
Permanent based Wood/Metal, opposite to mind. Really, craftsmanship is all that fits, which is why Im pushing for Mechanics, Machines, or something similar.
Machinery cannot be broken down into individual elements in that Wood cannot be broken into bark, core, fiber, leaves etc. Wood is made of discrete parts and components, ergo, machines are too. Many machines, clocks, watches, cars, carts, canons, boats, steamship river boats, cranes, etc etc etc are made from combinations of Wood and Metal.
Lets take Cannon. We will use Mechanics until something better comes along.
Cannon
6 :[Mechanics]
Permanent
2
Deal 6 damage to target player
This is similar to a many cards that use different elements to activate. The barrel is made of metal, as is the cannonball. The base or wheels are made of wood. It uses Fire to activate. It is affected by gravity, time, entropy, air, etc, but isnt an aspect of them. It is not fire, it uses fire as a trigger. It is made of wood and metal. It is a machine. It could be broken down into wood and metal parts, or even further to the components of earth and water and light, but it is nothing as broken down. It is a cannon, it is the unique configuration that makes it what it is. Armagio is a gravity master, able to call physical attacks to itself, redirecting projectiles and attackers through pulling gravity. A cannon is a Machine, that uses Machinery to perform an effect. It is what it is.
Anyway, unless we are doing 2 elements of wood and metal, we need a unified umbrella, Machinery, Mechanics, Tools, etc are good fits.