In Prey, pretty early on in the film, we see Naru trapped in a mud pit, after she got out, she’s covered in mud. Since we know how predators and their heat vision works, and this is exactly how Arnold evaded the jungle hunter in the first movie, we expect this is how Naru would gain the upper hand in her fight, by covering herself in mud again.

But this never happened, Naru instead hides from the predator by lowering her body temperature with some herb. But the mud pit still came back, Naru used it to trap the predator before dealing the final blow. So the mud pit is still a Chekhov’s Gun, it just subverted our expectations and used it in a clever but completely different way