http://wiki.uoroleplay.com/index.php?ti … ter_Bosses
There are three general categories of bosses. Bosses, Lesser Bosses, and Random World Bosses.
Bosses: The first are simply called ‘boss’ monsters. These are the hardest type of bosses to kill and will give the best loot. They are often found at the end of dungeons or through the world in special locations. These monsters will almost always drop an artifact or at least a unique special item. They have around a 100% chance to drop an artifact or special item. You will typically need 3-5 people to kill one of these monsters.
Lesser Bosses: These are weaker ‘bosses’. They are still fairly difficult to kill but not nearly as hard as a main boss monster. These monsters will not always drop artifacts or special item. They have around at 10% chance to drop a artifact or special item. You will typically need 1-3 people to kill one of these monsters.
Random World Bosses: These monsters can be either a full boss or a lesser boss. One boss will typically spawn per map at any number of random locations throughout the game world. Once the boss enters the game world it will likely wander around. You’ll never know which location it may end up at or where it will wander off to! These bosses will have the same loot rules as the bosses and lesser bosses listed above.