The Final Defense

I'm backing down from my original intent for today, of a major assault ending with destruction and the party back to the river. Instead, I want to consider a better setup to that. In the end, there should be a driving force sending the party out and back along their original journey. The question is, how to push them to that point.

Once they have defeated the dragon (an encounter that should be made more challenging, by the way) and returned to the fortress and the skirmish with the Grimlocks, they should be allowed a long rest. My thought is to put them through some type of siege before having them move on. In this light, several things need to happen. First, they need to be trapped within the fortress, i.e. surrounded. Secondly, their resources and their resolve need to be fully taxed, maybe even exhausted. Thirdly, some major element needs to be introduced that threatens to overwhelm them. And finally, they need to be presented with an opportunity for escape that is sudden and irresistible.

Step one is easy enough... after the long rest, they awake to find the valley floor crawling with a kobold army, sufficiently reinforced with larger goblinoids to deter a direct escape attempt. The details of this army are important, and need to be sufficiently balanced, but on a basic level, the answer is simple enough.

As for the next point, testing and taxing their resolve... a lot of that comes from the balancing mentioned above. To further that, I think the elements of a siege are important. The party will be defending on two fronts, through the fortress, and up from the tunnels. Multiple waves of attack, rather than a mass assault, will drain resources. Choosing different types of monster to make up the army will mean different styles of attack, which will tax varying resources. And time will factor in significantly, with short rests, day turning to night, etc.

I think it might be too daunting to have an around the clock attack, preventing the party from getting a long rest. It would be better to have waves come again and again, then retreat to plan a new strategy. Let the party get a long rest, then have a new wave of attacks come, perhaps from the tunnels.

The third condition, the threat of being overwhelmed, can be met in two ways. First, the waves of attack come in greater numbers from above and below, simultaneously. Secondly, a new danger enters the attacks. I'm thinking of giants or elementals. Something that brings a threat to the structure of the shelter as well as to the players' well-being.

Finally, some opening appears to draw them out and away. I picture a daring counter-attack, almost a last ditch charge out from the gates that pulls everyone there for the confrontation, allowing the party to slip away unnoticed through the tunnels. This brings out a problem... how can the party escape if they are needed to launch a counter-attack? The only solution is to introduce some kind of allied army that can aid in the defense of the fortress. I've got a kernel of an idea of how to develop this, but it needs a night's sleep to mull over.