Strange Undead

The party has encountered two creatures that appear undead but are clearly unlike any they've heard of before. The first was found within the Temple of Torm, standing over the body of High Justiciar Brynne Talhallow. The second appeared in the alley during their search for Erasmus Kallor and was later identified as the missing City Watch captain, Darian Windriven.
These beings do not behave like typical undead. They show signs of intention and purpose, and in Darian’s case, even speech—uttering the phrase, “Father says find the bard…” before attacking. Upon being subdued, both were found to have vine-like material inside their bodies instead of veins or blood.
Their origin, purpose, and the identity of “Father” remain unknown.