Jesper doesn't particularly handle the concept of having nowhere to run easily either, that is his go-to move when feeling overwhelmed. And it's kept him alive many, many times. But they're in the Horizon, right? No matter what happens, they can't die here. (Right?)

"We'll have to build our way out, somehow. We're not helpless, Mat, you did make a ladder."

Okay a ladder isn't super impressive but it still was helpful and it got him here. He has to think positively. Especially because when he glances over he can swear that the strange toxin seems to have grown. It could be in his mind so he watches intently, and genuine concern ripples through his expression that Mat can read, when he sees that it is moving. Slowly. But upward.

"We'll just have to keep creating floors and going up until ...." He doesn't know until what, until is the only thing he can think of.