Stirrings

There is an allure to Aron's Bowl that traps many adventurers in its web. The casual disregard for law and order, the ever-present element of danger, and the wide variety of personalities make the town a raw mixture of acceptance and desire.
The danger is in the attraction the town provides to all human emotion, but that danger can be as harmful as it is intoxicating. After several days, the relative peace is shattered by riders flying into town after a long night across the plains. Their reports quickly send rumors of danger and attack throughout the town, so that the party wakes to wild theories about the threat.
Danger, marauding hordes, violence and impending doom... all the usual... As cooler heads prevail, and the truth of the situation begins to chase the rumors out, it is revealed that late the previous afternoon, a large war party poured down out of the eastern mountains, rushing across the plain to ravage Garrett's Junction. Garrett's Junction is the on the river 50 miles south of Aron's Bowl. There is another outpost twenty miles further upriver that operates more as a trading post and tavern than a proper town. Losing Garrett's Junction means that outpost is cut off and surrounded, and the surrounding farms are unprotected, open to looting and savagery. Forces are being recruited to rebuff the attack. Your party's number is called, and you are expected to ride out to repel the threat.
As an added nod to your skill and expertise, Arvost, the ward boss for the neighborhood you are in, requests that you lead the way, riding hard to control the advance of the war band while they arm their recruits and head out to rescue the town. To persuade you to react quickly, they will reveal a chest containing 100 gold pieces, and a silver horn inscribed with decorative runes.
The horn is a Horn of Valhalla, and will summon berserkers to aid you in battle. They counsel you to take care and call the berserkers only in need, since the horn takes days to recharge. With their help, Arvost believes you will be able to hold the marauders until reinforcements arrive. In their mind, they are loaning the use of the magic item, but since they don't think to mention that, it is understandable that the characters see it as a gift rather than a loan. If they decide they want to hang on to the horn, have them roll a history check (DC20) to know the horn has a chance of exploding on use, and that they can use that knowledge to claim it has been lost in order to keep it. They will need to succeed on a persuasion check (DC20) to convince Arvost it is gone.
One of the riders will lead you back across the plains toward Garrett's Junction. The river swings toward the west before curving back to the south, so they will lead you directly across the plain toward the town. A hard day's ride will bring you to the outskirts of town by sundown. The rider will counsel you against attacking at night, but will suggest you could investigate the perimeter and discover the band's defenses. There will be opportunities to skirmish before morning.
The main force will arrive late the following day. If the band noticed the party overnight, or engaged them in combat, they will sally forth to meet them in the early morning.
Tomorrow, we'll decide what we're up against.