Yeah, it has a common enemy that likes to spam Sacrifice, which is a TPK even at max levels and they are notorious for being fast and usually getting a preemptive attack on you. It says something that the only non-king save point is in this area. Also, the bosses in the final dungeon will re-spawn if you leave the castle to save before taking on the final boss, so you have to do the whole area in one go more or less. To say nothing of the awful dungeon that leads you into this area... DQII's final area has the same notoriety as FFIII's last dungeon gauntlet.