As mentioned earlier, Giligatabbus Igglebix can be found on the iceberg island in the far East. It directly on an E-W line with the Tower. It is one of the tallest icebergs He is small and hard to see. Levitation is your friend here and in 3 of 4 of these "kill the SK" quests.
Hit me at 77 2850AC all defensive's maxed for level for anywhere from 9 to 397. Disarmed him before he was at 50% for the hell of it since I spam the key anyway.
Very easy, trio'd with 71sk, 66rngr and 70shm. Slowable and snareable. Casts Vampiric curse. with 2.1k ac max hit was 505. average hit was 225. No heals needed, got down to about 70% health. Follow the South chain of islands that runs along side the boat (no longer exists) path.
Went with my 68 pet with his 69 haste up. Took a few Elixir of Healing X and an Elixir of Speed X. Snared him stuck shadow howl on him. At first I chased him whacking on him but then I got lazy and just sat on my steed and let my pet do the job. Was no competition complete ownage.
Is immune to slow, and has quite a few hp, but an easy slow/duo kill. Forgot to get a Loc, but if you zone in and head to the Dock area...you will see two long chains of ice bergs, keep following the southern of the two heading SE and you will find him.