I had my own ideas rergarding the Bloodkin. Some should be simple, others not so much.
The Bloodkin will have been waging war against everyone and everything with a pulse long enough to understand one thing - lack of booze over many centuries has made them sluggish. However, since they essentially use mortal dwarves as livestock, they have a solution to their sluggishness - turning some of the cattle into Fledglings, arming the recently-turned, poorly trained dwarves, and sending them to the frontlines. The far more ancient Bloodkin would be pretty hardcore (if ponderously slow) fighters, since they have had centuries to train.
As for "something dangerous" to spit at targets, why not blood? Apparently harmless, until your entire military has been vampirized and starts chowing down on each other.
I also suggest that they use Cyclopes in much the same way that goblins use trolls, for extra !!FUN!!.
The iron flavor of blood shook him to his senses. It dribbled down his chin, still warm, dripping down onto his breastplate. His hands were soaked in it, up to the wrist.
Shank groaned. He had done it again. He had let the beast take control. After fighting the urge for months, he had collapsed, only to wake up in this very situation - wandering the hallways, with another dwarf's blood all over him. Had his victim survived? Probably not. When the hunger took him, he rarely stopped. It was like a battle frenzy, taking away all sense of himself and replacing it with a singular urge to feed.
He had given up on his work. Both as royal guard, and as royal spymaster. How could he manage a network of spies if he couldn't even manage his own impulses? And the queen was under arrest, locked away where none could get to her. Her sentence called for decades of imprisonment. In another time, perhaps, the irony would have pleased him immensely. Imprisoned in her own penal colony. How droll. The chief would have loved it.
Limbs trembling, Shank wandered the hallways. He wasn't sure where he was going. Sights passed him by without fully registering in his twisting mind. He passed other dwarves, some cursed, some mortal. He paid them no heed. His feet were taking him somewhere and hadn't deigned to inform his brain what their destination was.
Thoughts assailed him as he walked. Despite this entire ordeal and the horrors he had seen and done, Shank felt... stronger, somehow. His senses were sharper than ever as well. He could hear the heartbeats of the creatures around him, smell the delicious blood in their veins. His mace felt light as a feather, and his armor felt light as a pig tail cloak. And what had it cost him? The ability to eat? To drink? To die of old age? The price didn't seem quite so overwhelming anymore.
But then what little conscience he had left came back, and with it came the guilt. He had killed plenty in his life, but never had he murdered another dwarf. Nor had he ever taken leave of his senses like this. Was this the curse's fault as well? Or was he heading down this road even before that fateful day with the chalice of blood?
Shank's feet stopped. Looking down, he saw a bin, its lid most of the way off. He was in the stockpiles. Amidst piles of green glass trinkets, he saw a glimmer of gold. Not fully aware of what he was doing, Shank dipped his hand into the bin and retrieved the object, examining it in his hands.
A golden, featureless mask. It radiated power. Shank looked into its empty eyes.
And the mask told him all its secrets.
Somewhere in the distance, the howls of demons.
I'd like to request that the queen stay mostly unharmed for now. I gots me some plans for her.