is there any way to get a Skulking Cyst able to detect necrotic cysts?

[Ettina]

The Mother Cyst feat (http://www.realmshelps.net/cgi-bin/featbox.pl?feat=Mother_Cyst) grants a line of really cool, nasty spells, all of which first require implanting a necrotic cyst in the target. Once you've got them encysted, you can find them anywhere, inflict damage on them that can't be fully healed, use a spell that works like dominate person but with fewer ways to protect against it, and even turn them into a skulking cyst (http://www.realmshelps.net/cgi-bin/mainlist2.pl?name=Skulking_Cyst).

So, my question is - can you think of any way to grant Skulking Cysts the ability to determine which people have & do not have cysts, so they can be ordered to attack anyone without a cyst? I suppose I could simply place all cysts on the same spot where they can be deliberately shown to the Skulking Cysts (say on the arm just below the wrist, so they roll up their sleeve to reveal it), but I'd prefer something more slick.

[Ettina]

No one has any ideas?

[Mr Adventurer]

Are they undead? Can you Spell-stitch them with a spell that detects cysts?

[Ettina]

Are they undead? Can you Spell-stitch them with a spell that detects cysts?

Thank you!
Yes, looks like spellstitching could work. Normally you need a mother cyst to cast the cyst detection spell (http://eternal-madness.wikispaces.com/Necrotic+Awareness). But since the mother cyst is described as a focus for the spell and spell-like abilities don't have focuses, it would remove that requirement as well.

Plus, I could give them other nifty abilities, to throw something nice and scary at any non-encysted person who comes along.

[Segev]

I designed an NPC necromancer for my DM once. He used Necrotic Domination to send a living bomb into the midst of civilians, detonated him with Necrotic Erruption, and then Dominated those who became infected. He then let them plead with heroes to protect him...putting them in the way of the heroes who wanted to charge into melee. And would detonate one or more of them amidst the heroes.

Needless to say, not a nice man. But he was nasty and dangerous and played nicely on the party's desire to keep innocents safe.