Mexelis

Mexelis had hatched during the Feywild's Golden Age. The Nexus had become the centre of the universe, with people and creatures from all the planes and worlds travelling through it. His mother and father were on the Nexus' council, contributing to important decisions and serving the entire universe. Mexelis grew up in the bustle of this metropolis, meeting strange and powerful beings every day. Gods would use the Nexus to send their devout servants on quests to different worlds, adventuring parties searching for rare artifacts would come through a portal and leave after getting the information they required, and Dragons would come to pay homage to Mexelis' father, considered the wisest living Dragon.
His parents were not ordinary Faerie Dragons, but almost Deities in their own right. They had been alive for millenia and wielded considerable magical power. They bestowed this upon Mexelis, their only child. He was being raised to one day take their place at the Nexus' council and become the wisest Dragon in the universe. He took to this task quite well, exceeding expectations in his studies. He was a powerful mage and wisdom seemed second nature to him. However, Mexelis wasn't perfect. He had a bit of a quirky side and loved gallivanting around the Feywild causing trouble and enjoying life. Seriousness was a concept foreign to him, and he rarely seemed as wise as he was. When his parents passed away, and Mexelis was meant to take their place, he shirked his duties, preferring a life of adventure and fun.
He was rarely at the Council meetings, or at the Nexus alltogether. He hopped from plane to plane and world to world causing trouble and getting on the bad side of nearly every powerful being and Deity in existence. On some worlds he was soon worshipped as the God of Mischief. Mexelis enjoyed this life until one fateful day.
Trouble had been brewing between Bahamut and Tiamat for centuries before open war erupted. The two gods were both aware of the importance of the Nexus and directed all of their forces there, for the one who controlled the Nexus controlled interplanar travel. Every other Dragon God was forced to pick a side after the battle over the Nexus dragged on for months. Soon every known Dragon was in the Feywild, and the two Gods themselves arrived with their personal retinues. The following day the final battle was set to occur and the two armies gathered their strength.
Mexelis himself was not present during the battle. The rest of the Nexus' council had either fled or had died during the battle so far, but he was off in the Deep Feywild taking part in a month long orgy organised by a large group of Satyrs. When he arrived back at the Nexus the great building was destroyed. The final battle between the two dragon hosts released such a conflagaration of magic it tore a hole in reality, sucking all but the most powerful onto an unknown plane. The Dragon Gods had retreated to their homes severely weakened by the battle and the loss of most of their worshippers.
Mexelis spent the next few millenia trying to repair the Nexus somehow. He felt responsible for its destruction and the Great Dragon War. His father had always arbitrated major disagreements between Bahamut and Tiamat and Mexelis had failed to do so this time. He became a recluse, living in the Nexus, giving advice to those who came to seek him out but otherwise living alone.
All that changed when the Yuan-Ti invaded the Feywild. They were servants of Tiamat and he knew he could not let her control the Nexus, so he helped a group of adventurers seek out Bahamut and defeat the Yuan-Ti. Afterwards he asked this same group of adventurers to help him repair the Nexus. Times were changing.