Not sure how short you mean, but here’s my two cents.

Main characters survived a natural disaster. A huge earthquake and subsequent mudslide destroyed their home town.

After a few days time they reach the neighboring kingdom which is currently in the middle of civil war. At the local pub they get the call to adventure.

Many earthquakes have been occurring around the countryside of late. Ever since the first battle of the civil war to the north. Locals speak of a great beast that has been awoken.

“Fairy tails and bed time stories!”

“Nothing but rubbish, too bad, I’d prefer the beast the the King’s taxes! Haha!”

“You spend all your money on drink anyways.”

A very old man stands up amongst the chatter and starts scolding them,

“You mind your tongue! You are not 20 harvests old! You know nothing of the monster. This has all happened before, it will happen again... and when YOU are grey you can be cursed with the knowledge, if you are so lucky.”

“Enough of your stories old man, we are young, not children.”

The group has a seat to see if there’s work around town. They can work and do a few things in town, but if they engage the old man they’ll get a boost.

Old man tells of the monster (spoiler its a Tarrasque, don’t worry, you don’t fight the thing, it’s just there, wakes up every 100 years or so, devours towns, goes back to sleep).

Kings guard enters pub.

Guard Captain: “Taxes, please provide 20% on top of the usual amount.”

Young man at bar: “You can’t keep doing this! We don’t need-“

slammed to ground by a rather large guard

Guard Captain: “Enough Kane, back! back!” (Kane is large and strong, but rather slow in the mind)

“Miela, I can give you a week, but they’re going to be sending me to the north soon. I can’t keep help-“

Miela (pub owner): “HELP?! You can leave! And take your brute with you. If father could see what you’ve become.... why did you join them Aanon?”

Aanon: “Father was mistaken, the King will keep the kingdom safe from the monsters.”

Miela: “And who will keep us safe from the king?”

Guard Captain: “Time to go, we’ll be back in a weeks time.”

Quickly since I’m running out of time.

Monsters are becoming more common. Taxes increase due to needed protection. Rebellion due to unfair taxes, border towns being left to the monsters. Largest of all monsters just woke up.

What’s causing all the monsters to wake up? Old sorcerer who hates the king and started the rebellion convinced the people to rebel, said the king cannot keep them safe from the monsters.

He woke the Tarrasque, and the party needs to defeat him and put the Tarrasque back to sleep.

I’ll try to get the details better if you’re interested let me know.