Chimera Ant arc
After his fight with the Ortho Siblings, Ikalgo brings the fainted Killua to the clinic to have him nursed him back to health. Two days pass and Killua awakens only to be pestered by the greedy Nurse, who demands that he pay his exorbitant hospital bill of 1.8 million. Before payment, he demands access to the phone with another hefty service fee. Killua manages to get in contact with Gon and informs him of the situation he's in. With that squared away, Killua pays his clinic fees and leaves the underground clinic with Ikalgo by his side.
- The reason why Ikalgo knew about this place indicates that Gyro and his men often used this place for medical reasons.
- It is possible that the place has tight connections with the Mafia community due to its "underground status".
- It is unknown how the clinic can effectively evade the authority of the Republic of East Gorteau.