Cool! Definitely never would have thought of that.
In the spirit of giving this holiday season, I'll share my favorite Slave Collar recipe:
"Gingerbread Assassination Harpies"
1) Start with 1 whole fresh Black Harpy, available at Pangaea. A young bird is best (EA or MA).
2) With your Dwarven Hammer, stir 7 blood slaves to create a Black Heart.
3) Again with your Dwarven Hammer, combine 3 blood slaves, kneed until firm, and shape into 1 Slave Collar.
4) Stuff the Harpy with the Heart, and wrap with the Collar.
5) Season to taste with your favorite Misc item. A Ring of the Warrior makes a great garnish.
Your guests will be completely surprised by your thoughtful holiday gift!
-----
But seriously, Harpies are great candidates for Black Hearts: cheap, flying, 2 attacks, and nobody expects Pan to field assassins. Their biggest problem is poor morale, especially when in hostile dominion (9). Normally a Berserker Pelt is the solution, but Harpies lack a chest slot. Slave Collar fixes that, giving you a respectable-yet-disposable mage hunter.
Happy Holidays!
cleveland