Valley 1:What's The Theme Of Each Of The Six Colored Elements?
Fire is obvious, but also bits of light to a much lesser degree. In general, a theme of power, destruction, etc.
The theme here is life & earth. Most summon spells are here. This color will also use spells themed around dirt, rock, earthquakes, and the like. This is also the main color for healing spells.
Not just air, but also lightning. So anything stormy, or electrical. Yellow is also related to things that are robotic but NOT clockwork though robots tend to be yellow-based but also yellow-weak. This is also the color which represents all transmogrification spells: if you're changing your form into a bat, for example. Finally most of the movement-related augmentation spells that are not teleportations also go here.
Water and ice, mostly. Some extensions of that are obviously slowing type effects for ice, but you also get into area-of-effect type stuff with water "washing over" multiple enemies in a row, etc. AOE damage isn't unique to this color, naturally, but it is intended to be a larger theme here than in some other colors.
Illuminating dark areas is one major theme here, but you also get things like changing the time of day, or in fact even any sort of time-manipulation stuff in general. Some kind of clerical and "good" effects could also go here, like the ability to peacefully send vengeful ghosts to rest without "killing them again," etc. Any sort of "pacification" stuff would go here.
Entropy (in the physics sense) is the major theme here, and that is expressed in a couple of ways. First, you have have the obvious "evil" angle. Stuff centered around death, etc. But, primarily, it's focused on the decay and reorganization of matter/energy, which is why it's called entropy. This means that shrink, seize, and teleport also fit here logically, because all of those are transforming the states of matter and energy of other objects in powerful ways.