Day 2,145

They only wander the moors in winter, when the snow piles too high for us to leave our homes and the world outside becomes theirs until the next thaw. They're hard to spot if you don't know what to look for but by now we're seasoned veterans and we won't lose anyone this year.

Blood clear as their skin, clear as fresh glass til they feed. You can tell exactly how hungry they are by what traces of blood and meat are still running through them, colouring them pink and red against a sea of pure white snow. As the old saying goes, red sky at night and all that.

They don't make any sound when they hunt, half-crouched-half-buried beneath the snow when the sun's at its peak and all you can see for miles is blinding white with clumps of grass and heather further distorting the trails they leave behind as they make their way towards you.

It's not as simple as avoiding going outside, not when they figured out how to open doors five years ago. Our best strategy at the moment is setting increasingly complex puzzles up around our homes and placing whatever livestock we can spare in the way.

If they're fed enough they go back over the moors, back to wherever they hide when spring comes.