there could be a lot more specialized mechanics with coal than wood.
also isn’t coal supposed to be the direct upgrade for wood? a magic that is supposed to be good with heat magics? so if it gets an upgrade stronger than wood in some ways? isn’t that intended?
anyways, coal could perhaps explode into giant clouds of dust if it collides with solids or explosion, leaving chunks of coal everywhere, these chunk when lit on fire light the smoke on fire, similar to poison but only burn DoT so it’s weaker.
Coal
type: powder
damage: average (9.25x)
speed: slow (0.95x)
clash: neutral against liquids, explodes against energy (absorbing the energy) winning against light solids but loses on heavy solids. loses against magma
when coal hits/clashes, it explodes in a big AOE, leaving coal dust everywhere. this dust is combustible, dealing fire/scorched/melting when lit by a heat - based magic. liquid magics and wind disperse the dust. ash and sand increases the size of the dust mound
interactions: slows in water
drips coal dust (projectiles)
leaves coal dust
when hit by lighter energy magics (plasma, fire) wins the clash and gets set on fire.
coal is a sedimentary rock (i think) created using the fossils of dead plants and animals. the carbon compresses under the earth, creating a dark rock that is slightly powdery. coal is very flammable, so receiving contact with any heat magics will light it on fire.
Status effects: Sooted
increases damage from burns
Positive: increases damage from all energy magics and magma
Negative: decreases damage from powder magics, wind, shadow, and light
all energy magics, wind, and magma clear the sooted effect.
+ 
= petal blizzard magic