Eladrin

Eladrin were the most powerful of the elves, a subrace of elves who adopted the Feywild as their home. After centuries of exposure to that plane's magic, they acquired supernatural abilities not seen on most of their kin from the Prime Material plane and were effectively transformed into fey. Sometimes called noble eladrin, they were capable of changing their physical appearance and powers according to their mood, assuming characteristics of the seasons.
“To be not just ruled by emotions, but physically changed by them? Better to have no emotions at all.” — Mordenkainen
Description Fey eladrin were similar to silvanesti elves, but were considerably more slender. It was common for their eyes to shine, giving away their connection to the magic of the Feywild. Their hair and skin colors changed to reflect their moods, which could each be identified to a particular season of the year. How frequently eladrin changed their appearance was an individual choice. Some eladrin spent their entire lives in the same season or followed the seasons of the place they lived in, while others could change as frequently as once per day.
Abilities
A spring eladrin.
Fey eladrin were capable of teleporting over small distances. In an effect similar to the misty step spell, they could briefly step into the Feywild and shorten travel distances between two points, effectively instantly traveling over distances of up to 30 feet (9.1 meters).
The abilities that fey eladrin possessed were dependent on the season towards which they had the most affinity.
Spring eladrin channeled the joy of the spring season to all creatures around them, rendering them temporarily friendly and reluctant to attack the eladrin.[1][9] They were innately capable of casting a number of spells, including charm person, confusion, enthrall, hallucinatory terrain, Otto's irresistible dance, suggestion, and Tasha's hideous laughter.[1] Summer eladrin invoked the fiery aggression of the summer season, instilling fear to the hearts of all creatures in their proximity.[1] Autumn eladrin called upon the feelings of sharing and goodwill from the autumn season, avoiding violence when possible and using their magic to heal and help. While in that state, they were capable of innately casting spells such as calm emotions, cure wounds, greater restoration, heal, lesser restoration, raise dead, and sleep.[1] Winter eladrin entered that state when distressed by sadness. They irradiated their melancholy, sapping the will to act from all creatures around them. They could innately cast spells such as cone of cold, fog cloud, gust of wind, and ice storm.[1]
A summer eladrin.
Like their physical appearance and their powers, the impulsiveness and intensity of fey eladrin caused them to wildly change their personality depending on the season their emotional state felt closest to.
Eladrin in the spring state were joyful and playful, fond of mischief and playing pranks on other creatures. They were often oblivious to the dangers of doing so. In the summer state, which they entered when angered, eladrin became aggressive, vindictive, and furious. In the autumn state, fey eladrin assumed the role of conciliators, eager to resolve conflicts and to promote peace. They were also more compassionate and ready to help others and alleviate their suffering.
In the winter state, eladrin became bitter and pensive. They often cried frozen tears and irradiated a feeling of gloom that could be felt like a cold wind. Despite these variations, all fey eladrin shared many common traits, such as the respect for personal freedom, a great love for beauty and art, and a desire to surround themselves with beautiful objects.
Combat In all states, fey eladrin were proficient combatants who excelled at the longsword and longbow. However, it was in the summer state that eladrin reached the pinnacle of their speed and proficiency with those weapons.
Society
A winter eladrin.
Unlike other elves, eladrin did not feel a pressing need to return to Qualinost. Instead, they found themselves more strongly connected with the Feywild. There, their cities displayed extraordinary feats of elven architecture, blending magic, nature, and structures into awe-inspiring landscapes. The culture of eladrin civilization was older than any other elven culture in the multiverse.
Some eladrin believed that, if they led a life of upholding the ideals of the Feywild, they could reincarnate as members of the Seelie or Unseelie Courts, or even as archfey.
History The eladrin were originally elves who found refuge in the Feywild when they were attacked by ancient ogres in the age of starbirth. Unlike other elves, who then decided to move on to the Material plane, the eladrin chose to remain in the Feywild and adopt it as their home. Centuries of exposure to the wild magic of the Feywild changed those elves, imbuing them with the flexible and mutable nature of the plane, turning them into eladrin.[4] While some eladrin managed to remain humanoids despite these transformations and only acquired some additional supernatural abilities, most were completely altered by the plane, changing into fey creatures.