No one said anything about sneaking, and IIRC at least one of you has a light source. So I'm going to roll with it under those assumptions.
As you enter the cavern where the ant-men had been running their bucket-brigade (they are no longer here), you see just entering the same cavern on the other side a trio of unfamiliar faces. A short woman, at best coming up to most of your waists, and adorned in a white robe with a set of gold-rimmed spectacles sitting on her face, is accompanied by two muscular albino humanoids with tusks. The two albinos look identical, and both have their long white hair hanging in many, long thing braids from their heads, making it look sort of like a mass of wires. Each wields a long spear-type weapon with a hook on the end of it.
Their lips pull back into a mocking sneer at the sight of you, and the small woman standing just behind them says
"Oh, so who have here?" Then seeing Cyrus' glowing eyes and blade she says
"Ah, a group of lost exiles. I might have known that fool Centarus would have fallen to such rabble. Give me his Spellkey* and I'll consider letting you live." Her voice is louder than you'd expect from her size, and her tone is one of someone used to not being questioned.
A Spellkey is the focus which lets state-sanctioned magic users cast their spells. Even though they are attuned to each individual, and not useable by anyone else, they are still jealously guarded by the State, presumably in fear that someone will reverse engineer them.