A few days after the raid against the Horseman of Plague, the next horseman appeared or rather was discovered. It was the Horseman of Death and it actually spawned near south area where the castle of the undead is located.
A guild known as the Masked Death, which is mainly filled with undead players, set up the raid against it. Since the Horseman of Death is near the castle of the undead, many undead players also came and got recruited by the Masked Death guild. They managed to build a raid party that had a strong number of one thousand.
One would think that they are just throwing away their lives when the Horseman of Death has instant death skills, but they are undead. Undead are not affected by instant death spells or abilities but that does not mean that they do not get damaged. They will not get executed immediately but probably drop to red health depending on their defenses.