Giving him 4 spiderling eyes (drop off the jungle hatchlings in the zone) gives you +faction with Grobb merchants and 1 copper, 1 silver, 1 gold as your reward.
Well, just helped take him down, took us over 2.5 hours. when i got there, about 30 min after they started, we had 4 war's 1 pally, 1 bst, at the end we had those 6, 2 rangers, and 1 cleric. He took a LONG time to take down, had him drop a flameage gem ( i think it was flameagait), and also a intestine necklace. Even though it was really long, it was a lot of fun.
Charmed and hasted one of the high level ogre guards around the arena and put him attacking the Exterminator.
Exterminator dropped to 90... 80... 70... 60... all within about 2 minutes.
Then he stayed at 60. Exactly at 60.
I was standing about 3 feet away, just out of aggro range, I had a perfect view of his health.
I hung around for another 4 minutes or so, and it stayed exactly at 60. I dropped a couple 1K nukes and it stayed exactly at 60.
I conclude that they have special coding that prevents them from ever dropping below 60. Yet another creative method to prevent players from killing quest mobs.
This guy is not 61 - he cons blue to my 54 troll SK.
Don't know his faction though - I'm warmly with all the trolls and DEs and he cons indifferent to me.
This guy is possibly currently bugged - I descided to kill him just to see what those axes he was holding were and after doing over 5K in damage to him, his hitpoints still had not dipped below 99%.
On the positive side though, none of the DEs bothered helping him when I pulled him through the gates, although they were both green to me at the time.
All of my spells stuck without issue as well if someone wants to try him - darkness, boilblood, heartflutter, my spear line and lifetaps - HT also hit for full damage.
This guy also hits very fast, although he didn't hit for more than about 110 with me having an 1147 AC at the time.