Hunter x Hunter features a variety of enigmatic and fascinating villains, most of whom play a significant role in the lives of the main characters. While the Chimera Ant Arc brought the spotlight to the complex Meruem, there was one other individual who was on screen for a very brief period but intrigued the curiosity of most viewers - Gyro.
Gyro is the founder of NGL and a man who many believe to be the secretive main villain in Hunter x Hunter. Nothing is known about his appearance or true personality, with major assumptions being made based on the narrations of his life as well as his reputation among his followers.
As mentioned, during the Chimera Ant Arc, Gon and Killua were in Doli City to complete their training with Knuckle and Shoot. In the midst of their battles, the scene suddenly shifted and introduced a supposedly malevolent individual in the same town as Gon called Gyro.

With little context, Togashi went on to explain the life of Gyro, who had been raised in a construction camp by an abusive father. Forced to work before he could even talk, Gyro lived a restrictive lifestyle with his single, alcoholic father. He knew little of the outside world, and could only use the bathroom twice before 9 p.m.
Gyro was ordered by his father to not create trouble for anyone else and was even beaten up for making too much noise while sleeping. As a result, he lived reclusively, though remaining obedient to his parent. This was because of two reasons: Gyro’s father had nursed him throughout the night when he was sick in the past, and his father had never told him to leave.
Unfortunately, Gyro’s illusion soon came crashing down. During a disagreement with another boy, Gyro was told the harsh truth of how his father was merely using him for labor and money. He also discovered that it was an old man next door who had cared for him during his time of sickness, while his father, drunk, paid no mind to whether his son lived or died.
While Gyro launched himself at the boy out of annoyance at his words, he was easily beaten up. At that point, his father passed nearby, saw his son, and walked away with complete indifference. This was the last straw for Gyro, who realized the universe did not care about his existence. Believing his life to have no worth, Gyro killed his father with a hammer, took his money and left.
Nine years from then, he established NGL, and in another nine years, it became a nation ruled by him. However, during the Chimera Ant attack, Gyro was eaten by the monsters and became an ant himself.
Why Gyro is one of the most dangerous villains in Hunter x Hunter
Even though he has never been properly shown in Hunter x Hunter, everything mentioned about Gyro is enough to place him among the most dangerous individuals in the series. He is a man disconnected from the human race, hoping to spread evil throughout the world.
For its sake, he developed D², a mysterious popular drug that was believed to be part of his plan to plunge everyone into darkness. Even after losing NGL and being turned into an ant, Gyro’s sheer willpower allowed him to retain his humanity and avoid being bound to the Queen or the King.
The last known news about him was provided by Welfin, who claimed that Gyro was trying to establish a new nation in Meteor City. His charisma still attracts his former followers, as Ikalgo and Welfin continue carrying his memory and remain loyal to their king.
Therefore, even without knowing details about his Nen and combat prowess, fans understand that Gyro is a determined and resilient individual who dreams of creating evil. It was no coincidence that Togashi specifically pointed out Gyro’s presence in the same place as Gon during Hunter x Hunter’s Chimera Ant Arc, and he is now in the home of the Phantom Troupe, Meteor City.
While there is no guarantee that the mangaka’s vision for Gyro will ever be fulfilled due to his health issues and Hunter x Hunter’s irregular schedule, there is no doubt that Gyro is meant to be an immensely formidable figure in the series.