The Haunting of Calrow Ruins: Conclusion
If the characters perish, are transformed into gibberlings, or retreat for more than a month, then the gibberling brood mother accumulates enough power to break entirely free of the grim tapestry, leading a horde of her foul children to wreak havoc in the countryside.
If the characters liberate Calrow Ruins from the gibberlings and slay the gibberling brood mother, the threat is vanquished. A conflict may form between Lord Polding and Lady Bridgitte Nydaridien as to whom will claim the keep, and the characters may become involved for either side, or perhaps decide to establish the keep as their own stronghold.
Further adventures await: the characters may be forced to seek out the Murkhorn trolls for the secret of how to destroy the grim tapestry, or to face the troll clan if the gibberling brood mother managed to escape and consolidate its power among the trolls. They may scour the caverns beneath the ruins for the lost onyx ring, or sealing a forming breach to the outer planes beneath Calrow Ruins.