Just duoed with tier 2 healer merc as a level 77 SK and fight lasted <30 seconds. With 2850AC max hit was 1036 and I was only hit that much 4-5 times; average hit was about 350. I would say a lvl 70 could duo him with a healer merc.
FYI before hail con is different then after hail con; at 77 before hail he was green. After con he poofed and a light blue version popped and started wacking on me.
As it has been stated he walks on the beach by all the skellys.

Silithis's Head