come up with a magic system, and then using that magic system describe how some magical creatures have evolved to be what they are.
The magic system in this fantasy world is based on the manipulation of energy fields that exist within the environment. These energy fields, known as "aether," can be harnessed and manipulated by certain creatures and individuals known as "aethersparks."

Aethersparks are born with the innate ability to sense and manipulate these energy fields. They can use this ability to perform various feats, such as creating illusions, levitating objects, and even healing others. As a result, aethersparks are highly respected and sought after in this fantasy world.

One magical creature that has evolved as a result of this magic system is the "aetherwing." These creatures are small, winged beasts that have the ability to manipulate aether in a unique way. They can create powerful gusts of wind by harnessing the energy fields around them, allowing them to fly at incredible speeds. They also have the ability to create small whirlwinds to protect themselves from predators.

Another magical creature is the "aetherbinder." These creatures are large, quadrupedal beasts that have the ability to bind and control the aether around them. They can create powerful barriers that protect them from harm and can also manipulate the aether to create powerful blasts of energy to defend themselves. They are often used as mounts or guards by aethersparks.

Lastly, there are the "aethershapers." These creatures are small, serpent-like beings that have the ability to shape and mold the aether in their environment. They can create intricate illusions and even form solid objects out of the energy fields around them. They are often used by aethersparks for entertainment or as companions.