He seems to be a relative common spawn ; from my ~10 solo kills exeprience , Iwould say he drops the Miniature Nosering as common , the Ring as uncommon , and the no drop 2HB he shares with a few named as rare (hopefully ) . Never saw the range slot .
There are 2 types of ulthorks in siren's grotto: 'a rampaging ulthork' and 'an enthralled ulthork'. 'a rampaging ulthork' does not drop the nosering or 2hb.
hits for 240 max avg. hits were 113-166 but never doubled/tripledquad (whatever he does) for over 200 highest dps he had was (240 186 233 133 240 160 207 166 113 240 160 213 153 207 193 110 146) that were his very last hits doesnt rampage or enrage flurry or any of those stuns killed with: 2boxing 57 monk tanking 65 druid healing (only had mana enough to nuke once with FT15) droped the ring....
Been hunting this zone for a few weeks and not once has this guys popped in. I have seen him on tracking a couple of times but he was in deeper towards the castle. Didn't try going in for him at the time since it weas reported that he would spawn in any bulthar spawn point. Either this info is incorrect, or he is extremely rare. I usually do the front entrance of the zone (CS side), the seahorses, swordfishes in the front pond and under the waterfall, and the walrus's, manatees, bulthars and moktors that spawn around it. I have done quite well here now, but no enraged ulthork. I have gotten the enthralled ulthork several times tho.
Anyway, if anyone has specific info about this mob (since his drops are what brought me here in the first place) I would appreciate it if you would share. Thanks