Gordon Freeman

Buildings in old towns like this are often so cheek-by-jowl that it doesn't really make that much of a difference which house you're in. The crawl space in the attic leads through a broken wall (painted with an orange lambda, which provokes a small smile from Gordon) into another building entirely. Up ahead, a man-sized gap in the slanting roof lets the moonlight in.

... enough to light up the zombie that's just lunged to its feet.