The Six

Also known as "The Strangers," The Six were powerful creatures that spawned during the Summer of 2008 as part of the Warriors of Destiny event cycle.

Their purpose, who they work for, and other key pieces of information are largely unknown at the time of writing (January 2009).

Their names and spawning locations were:

Only one spawned in each location.

They were difficult to fight. Their attacks were heavily fire-based, and they could cause pet Dragons to go wild.

They were sometimes capable of one-hit-killing Player Characters, and also killing pets extremely fast. Each of them initially spawned holding a weapon, usually a halberd. The weapon however had limited durability (60/60 or so). Fighting them with a Mace Fighting character would usually lead to their weapon being destroyed (from reaching durability zero) far before the enemy was dead. At this point they would start to attack with bare hands, at which point they would typically do enough damage to one-hit-kill player characters (well into the triple-digits in a single hit).

The fiction surrounding The Six was purposefully ambiguous as to which side of the conflict they were on. However, they were certainly capable of evil acts, as two of them spoke casually of the pros and cons of committing genocide upon humankind, and one of the murdered several people outside Despise. It did sound as if they might be in search of something.

They would not attack players until attacked themselves. However, their area effects indiscriminately injured player characters, and they were hued red, a traditional means of noting that an NPC is evil or hostile (or both).

For loot, they left strangely-shaped gemstones and A Magical Lockbox. Opening the box caused all the items within (large amounts of peerless type loot, potentially including all relevant artifacts up to and including the Crimson Cincture) to fall to the ground (where anyone could grab them). The box itself was very valuable and in high demand among players, due to the difficulty of finding and defeating a member of the six - and also the difficulty of picking up the box, which would also be left on the floor. The box would be immovable for a short time after it dropped, often leading to a crowd of PCs trying to pick it up at the same time.

The Six left no corpses. When they were defeated in combat, their body would disappear, and the shape of an Ancient Wyrm could briefly be seen. Some of them would smack talk, taunting the characters who had slain them, assuring them that they had not really won.

The combination of this dragon effect after they died, the effect they had on draconic pets, and their use of fire suggest that they might be powerful dragons in their true form, but taking on the form of humans for their visit... or perhaps just a special race with power over dragons?

Either way, it is worth noting that they bore obvious similarities to the Crimson Dragons, who appeared in another Chapter of Warriors of Destiny. Among other similarities, they both cast the deadly "Vas Flam" ("Rise Flames") spell, causing walls of fire to erupt, and they smack talked in very similar ways.

Sources:

http://town.uo.com/bnn/article_593.html

http://town.uo.com/bnn/article_594.html

http://www.uoherald.com/news/news.php?newsid=385

http://town.uo.com/bnn/article_595.html