The top frog himself, he is found deep in the depths of Lower Guk, and is guarded by Guk knights I believe. The king is a paladin, and has a ton of hitpoints.
This mob spawns at -105 , 15.22. -232 Farthest South Western room in zone.
Sometimes you can go for ours without even seeing this guy. I've also been there when he spawned three times in a row and had mith 2 hander two of those three times, rare spawns are funny like that. And as for his LoH, when you see his health drop to near 1/4th, clerics and enchanters break out the stuns, an wizards start with the ice comets unless you want to start the whole fight all over again, which can mean zoning or evacing when trying to break the room from full spawn. Also, one way portal behind the throne that sents you to upperguk near the Innotule entrance. It is also known that this portal is very buggy, causing people to go thru it without actually zoning, this happens seldomly with most zone barriers but seems to happen more so here. Be prepared and zone thru a second or third time ASAP if this happens.