Dungeon difficulty: "Difficult mode".
This dungeon was easy as long as players understood the mechanics behind it. As such, there was no need for the team to attempt Heroic mode; they went straight for the Difficult mode.
As for the Nightmare difficulty, the Bloodmage in this mode would be able to cast a fearful spell – Death and Decay. This skill would instantly kill any players, including the main tank.
If the skill was casted on the main tank or healer, the team would wipe. If other people sacrificed themselves, the rest of the team would be able to pass through. This meant that the Nightmare mode relied heavily on luck, but Ruling Sword really needed a First Clear right now to maintain their popularity. There was no need for them to test their luck.
In Dawn, many Instances were either dungeons or chambers. Spider Lair, Death Mines, Howling Caves, Blackfathom were all good examples of this.
However, the graveyard was an exception.