|The Ortho Sibling|
|Relative(s):||Chimera Ant Queen (mother)|
|Occupation(s):||Chimera ant officers|
|Nen:||Dart De Darts (死亡遊戯 lit. Game of Death)|
The Ortho Siblings are two Chimera ant officers who are a brother and a sister. They live in an underwater cave partially filled with water in East Gorteau.
The siblings have features of aquatic animals. Both of them have scales covering their legs as well as webbed feet. Scales also cover the brother's arms while the sister's are left bare.
After Remora successfully attaches the Bar Double Bull badge conjured by the sister on Killua, the brother starts throwing his fish-like Nen darts at Killua and seriously injures him with ease. However, Killua figures out that the finishing dart is aimed at his head. He then uses his Godspeed technique to greatly increase his reflexes, stops the dart when it just touches his skin and pretends to be dead. Thinking that he has been killed, the siblings come out of their hiding place to check out his body but they are taken by surprise and decapitated by Killua.
Dart De Darts: Their nen abilities work in conjunction--the sister creates a tag that when placed on someone, will link her brother's dart board to the target. The tag cannot be removed until the game ends, not even by themselves. The brother can then shoot the fish-like darts made from his aura at the board and cause damage to the target according to where the darts hit the board. Because the darts that will pierce the opponent's body do not have a physical form until they come into contact with it, they are impossible to block. The siblings run a considerable risk playing the game since if the older brother misses the last shot to end the game, all the damage accumulated on the target until that point will be carried over to themselves.