Odo the Blindwatcher, having already been killed in the past, is now summoned as a ghost worgen by Baron Silverlaine when his health is brought to ~50%. He does not drop any loot nor does he say anything during the fight.
He lived in the dilapidated wooden structure hanging precariously off the side of the keep with two pet bats, a Blood Seeker and a Vile Bat. Although he lost his eyesight long ago (hence his nickname), he had adapted to using his other senses, much like his pets.
Abilities
[Howling Rage]ωϖ—Physical damage dealt is increased by 10. (Once)
[Howling Rage]ωϖ—Physical damage dealt is increased by 20. (Second)
[Howling Rage]ωϖ—Physical damage dealt is increased by 35. (Third)
Odo was pulled with his two pets. All three had to be battled at the same time. As Odo got more and more damaged, he would cast Howling Rage, a buff that increased his attack power and made him grow in size. He would cast it 3 times, each new Howling Rage more powerful than the last. When he cast Howling Rage, his pets got the same buff. For this reason, the bats had to be killed before moving on to Odo.
Patch changes
Patch 4.0.3a (2010-11-23): Now a summoned mob rather than a boss.