is a unique encounter, it will spawn randomly after it is killed. This is one of the most neglected mobs, since it's loot is rather limited. Like other unique encounters, it has too much HP and high HP regen. A level 150+ player can solo him.
It is located in Greater Tir County (275,1940) and it is level 115. No special tactics are needed to kill it. Located near the zone border it offers retreat possibility if player(s) start to doubt he(she/they) can kill it. With high HP regen, strategy of zoning to heal doesn't help, since by the time a player returns the mob should be fully healed.
It also drops implants, rings and bracers. Melee Nball isn't 100% drop, but is fairly close. Only 3 or 4 Handguns Nballs are reported to have dropped, right after those mobs were introduced in-game, but nothing more since then.