For context
Darktide have something similar in Daemonhost…except unlike Witches these enemies are pretty trivial and harmless
But looking at what Chaos, Skaven, and Beastmen have in their canon roster… what’s an enemy that’d remain largely dormant and can snuck around, but is strong enough to **** up an unprepared team of Hero-tier characters? Closest I can think of are the patrols, but those are a group of elite enemies.
Forsaken unfortunately suck hard. And FS restricted themselves to Nurgle, otherwise a Herald of Slaanesh would have been pretty perfect.