Also known as "a deserted mine" has a troll outside at 78, 22, -423 who gives access to the zone.
Short version: 3 minutes after NPC finishes talking and starts casting spell for boss a Greater Symbiant group x2 will spawn near the NPC, kill them, this is a dps race, you have a maximum of 2 minutes 30 seconds. Repeat for next two groups that spawn (level 52 Symbiant Lord x2 group and level 52 Symbiant Protector x2 group), entire group must be dead in less than 2 minutes 30 seconds or the npc will gate out without completion of the spell leaving the boss largely unkillable.
After the last group dies the NPC will finish the spell and gate out, you have a few minutes till the boss spawns in the big alcove at the rear of the zone.
The boss is alone and level 54 Tremblar the Behemoth which is a Raid x4 mob.
You will have time to heal/buff/repair between fights.
You can expect the main focus of the agro of all of the groups to have their weapon destroyed each fight. They destroy armor/weapons. Keep spares or keep repair kits.
(As a 62 shadowknight I was able to duo zone with a inquisitor merc.)
http://everquest.allakhazam.com/wiki/Orcish_Mines - Strategy for killing the boss.