Viktor the Vile

Ruins of Lordaeron
Beyond King's Alley, choose the side encounters before finishing with Rath'mael. Approach the market statue from Lordamere Overlook for The Abandoned's wave event. Viktor the Vile is optional: the chimney in the house southwest of the overlook starts the waves that bring the boss out, so recover health and mana before touching it. Clear nearby groups before engaging Bjork's central patrol rather than combining the fights.
Viktor the Vile
Viktor the Vile tests resource management through the chimney event, followed by a boss whose Leech Poison restores the health it drains.
Abilities

Leech Poison
Drains 15 health from an enemy every 5 sec. over 40 seconds., transferring it to the caster.
Remove Leech Poison if possible so Viktor does not regain the health it drains after the chimney waves have already spent the group's mana.
Tank- Be ready to take Viktor as soon as the chimney waves bring the boss out, before it reaches players recovering from the waves.
Healer- Preserve mana through the chimney waves for Viktor's arrival. Cleanse Leech Poison if you can so the boss stops gaining health from its target.
Damage- Keep resources for Viktor rather than spending everything on the chimney waves. Focus the boss when it arrives so Leech Poison has less time to restore its health.