The Time Lord is a mysterious NPC in the history of Ultima and UO. He has been spotted several times and has had major impacts on the course of events. However, his exact nature and purposes seem to remain largely unknown.
He brought the news to Lord British of the different Shards upon which we all live, in a conversation overhead both by Lord Blackthorn and Sherry the Mouse. Their overhearing of that conversation altered history in major ways. Anger over a deal made between the Time Lord and Nystul led to the founding of the Council of Mages Faction. He was said to be the mysterious figure that appeared at certain dimensional Rifts created by Blackrock. During this event, due to a highly amusing but, this legendary supernatural creature could teach Player Characters in the Blacksmithing and Arms Lore Skills.
Most recently as of the time of writing (January 2009), the Time Lord was seen near the Blackrock Detector, for part of the Mad Mage event. He engaged in a brief, unfriendly conversation with the Shadowlord of Hate, Astaroth.
The role he will play in the Warriors of Destiny event cycle is as unsure and ambiguous as is the role he has already played in Britannian history.