Sudden Dark

Castille's torch hisses out, and darkness plunges over the scene.

Castille and Humfred have low-light vision, but that doesn't help you if you're not near some source of light. They cannot see at all. There is a soft light coming over the lip of the vat - presumably a candle or a lantern that the warforged put down before he began hsi silent climb. But that soft light is not enough to see anything with. Anything at all.

Castille and Humfred are blind for all intents are purposes.

And so is the warforged.

"Hey!" you hear the warforged barbarian yell. There is fear in his/its voice. "HEY!"

"Magical constructs have darkvision," Humfred whispers in Castille's ear. "But living constructs like the warforged do not. They do not even see as well as we do, they have the same vision range as a human or a halfling."

Kaspar of course, is a half-orc. He can see perfectly at the moment. He can see the terrified expression on the warforged's face. Kaspar is the only one of the four here who can see at all.