I heard this guy was a meat grinder. Real pushover was my experience. Clear some space to fight so group members can spread out, because when Deepblade does his targeted AE damage, you don't want it hitting multiple people at once. Killed him effortlessly 3-boxing warrior, beastlord, druid, plus 2 wiz mercs and 1 cleric merc. Didn't parse it but he sure seemed light on hitpoints; died fairly quick.
One of his placeholders, thelara of Oseka, is not presently listed in the bestiary.
95 enc/95 monk boxed. Enc : t2/t3 raid gear, Monk:group gear. Had a bard too (raid gear). i spend most of my time with this bard, and it seems that they make killing a namer very easy, Heal mods, AC mods, takes the Yo-yo out of the heath bar. if this guy is a problem for your group, my advice : get a bard. xD (bard used a spell reflect and this guy 3x in a row ate his own nuke :P )
Deepblade seems to have 2 ph's. They can be a myrmidon of Oseka or thelara of Oseka. In Sepulchre west in the Tides section. down the water and then to the north east area. the locations are approximately: (+451 x +2493 x -239) and ( +398 x +2370 x -222). The first is very close to the waterfall and the second is higher up the ledge closer towards The Relic of Oseka. He uses an attack called Tidal Surge. 45 curse counters. And has an AE attack tidal blade (54k). Tiddal Surge by itself can kill your group as the previous poster stated. 35k+ multiple times unless you get it cured. Our single cleric was hard pressed to keep us all group healed ( which also cures it).
This mob dropped my fully raid geared group in about 5 seconds. AE'ed a 35K spell 3 times really fast. I'm sure there is a way, but wow what a group mob.