|The Husk, Foulmane & Scarlet High Clerist|
|Scarlet Interrogator, Scarlet Executioner & Scarlet Smith|
|Dreadwhisper, Lord Maldazzar & Scarlet Judge|
As someone was kind enough to mention in the comments, there is one additional rare in this zone that I forgot to mention, and that is Putridius the level 40 undead abomination. Putridius is technically in Scholomance (even though he is outside the actual instance). Because he isn't listed as actually being in WPL, he doesn't show up on SilverDragon or even on WoWhead's list of npc's that reside in Western Plaguelands. He's definitely still around though, and when he is up he's very easy to find. He doesn't patrol at all, he literally stands there right in the entryway before you turn left into the instance portal.