Story? What? We haven't got time for that, just pick up a weapon and report to your posts you idiots! Can't you see those barbarians charging at us through the trees to the north? I doubt they care very much for a story, in fact, I reckon they're just here for our heads. Yes, of course that's why they're here - can't say I remember the last time they made a social call.
What barbarians? Are you simple? How long have you been stationed here? Oh that's right, you're one of them that arrived yesterday. Well, consider this your induction:
We're getting attacked by a horde of damned savages. Eight feet tall, long messy hair and matted beards. They like to swing heavy maces to crush a man's skull, or sometimes they like to get really fancy with an axe and cleave a man's limb. They cover 'em selves in tattoos of all kinds of nonsense, they reckon it protects 'em from our arrows. Well, I ain't seen it work yet, that's for sure.
Anyway, enough loitering, head to the armoury, get yourself a weapon and some armour, then get to the battlements. They'll be hitting us from the north first, like they always flippin' do, so that's where I'd suggest you go congregate.
OI, and remember! This castle is the only bloody thing keeping your families back home safe and sound, so if you're thinking of running, you better hope enough of us are mad enough to stay. Otherwise... well, you ain't gonna get far, let's put it that way.
Didn't you BLOODY hear me? We haven't got time for this rubbish. Grab a frickin' weapon, head to the blasted walls and get ready! GO!
What's in the armoury?
Medieval stuff! See examples below - but choose whatever you want, so long as it don't shoot lasers or bullets.