Urgaloth
Urgaloth is the title held by the nominal leader of the yugoloth race. The urgaloth rules from the Siege Malicious in the Wasting Tower of Khin-Oin in Oinos. The urgaloth is the nominal ruler of Oinos and the Blood Rift.
Canonically, the title was oinoloth (also oinodaemon), but in 5e for some reason they made oinoloths a type of yugoloth rather than an office.
The current urgaloth is Anthraxus the Decayed.
Pathfinder
In Pathfinder, the leaders of the daemons are not the urgaloth and the GOG, but rather the Four Horsemen. A fifth Horseman—known as the Oinodaemon—is rumored to exist.
Seat
The urgaloth's seat of power is the Siege Malicious, a magical throne at the top of Khin-Oin. The only way to become the urgaloth is to oust the incumbent. However, it doesn't seem that you need to outright kill them—if you can get them to fuck off, that's good enough.
Known urgaloths
- Infestix, the first urgaloth
- Anthraxus the Decayed
- Mydianchlarus
- Phraxas, who revealed himself to really be Anthraxus
- Kexxon
