Running a fortress siege.

[LoyalPaladin]

Good mid-morning, Playground!

I'm going to be running a large scale encounter that will be taking roughly two sessions to complete. I've got a mid level party with a small mish mash army that is trying to defend a city from an army of demons (not devils).

I was hoping to get a little help with big battle rules. I had played in an encounter like this before at the Tower of High Clerist in Dragon Lance. But it has been some time. Do you have any good ideas? Or good demon siege ideas?

Thank you as always!
-LP

[Tvtyrant]

Are they just demons or does it include tribes/summoners? With Devils or tribes you could use the sacrifice rules from Book of Vile Darkness to murder weak allies to planar bind stronger ones. Works well with captives too.

For the actual siege part, my suggestion is that you have the demons lull about outside of attack range, then make rapid strikes using their greater teleport to try to take the castle. The party is thrown up against the strongest demons in the teleporting group, and if they win the demons run for it. You can even have attacks where the demons have short civil wars over who will be in charge when the party kills the current leader. The big thing is not to try to make it like a human siege; demons don't have strong bonds to each other and so lack to cohesion needed for long term war. Instead they will rush recklessly before panicking and fleeing.

[Surpriser]

Demons are uncoordinated, without complex plans or lots of patience, but that does not mean that they are unintelligent.

I imagine they would not go for an extended siege. Rather, shock troops would teleport into various points throughout the city and spread chaos and destruction. I heartily recommend using Jovocs (MMII), you will see when you read their description.

While the defenders (and possibly the PCs) are occupied, another wave of more intelligent demons pops up at strategic points (the keep, the gatehouses, armory, temples, water supply, storehouses,...) and uses the general confusion to break through the line of defense and clear the way for the rest of the army.

If teleporting is blocked somehow, you can use flocks of Vrocks to deliver other demons via the air (e.g. in sacks padded with Dretches).

Each group should have at least one commander, who will rather die than run or be captured alive (he knows what would happen to him otherwise) and lesser demons who will do the same while the commander(s) stand and run immediately should they fall.

As for the mechanics, don't treat the army as individual units. Prepare attacks of smaller groups on strategic targets (and some random encounters for wandering shock troops) and let the PCs fight those groups. The rest of the army only serves for dynamic events (siege weaponry, barrage of missiles on the wall, sudden reinforcements dropping in...).
Alternatively you could let the PCs control the whole army of defenders (or parts of it). But then, the mechanics of D&D are no longer suited for this.

[Unseenmal]

I've always used Warfare for Beginners (http://www.enworld.org/forum/showthread.php?314572-Warfare-for-Beginners-(a-battle-system-for-the-Pathfinder-RPG)). It also has a Part 2 (http://www.enworld.org/forum/showthread.php?314693-Warfare-for-Beginners-2-(Pathfinder-RPG))

These rules are for Pathfinder but there is a rule-set for 3.5 as well. I don't have the link for it, just a Word Doc. I can send it over if you want.

It's a mass battle system that gets the PCs involved in the larger war as more of a tactical/spec ops squad. It works on Victory Points. You set the VP total that either side needs to get to to win. Then the PCs can perform missions/quests to accumulate/lose points depending on if they succeed or fail. There is a table that you can use to randomly roll for missions or you can cherry pick. They could perform sabotage, spy, counterspy, assassinate an enemy ranking official, etc. It gives daily events like weather or reinforcements that can change the battle.

It's worked well for me when I've gotten to use it.

[LoyalPaladin]

I've always used Warfare for Beginners (http://www.enworld.org/forum/showthread.php?314572-Warfare-for-Beginners-(a-battle-system-for-the-Pathfinder-RPG)). It also has a Part 2 (http://www.enworld.org/forum/showthread.php?314693-Warfare-for-Beginners-2-(Pathfinder-RPG))

These rules are for Pathfinder but there is a rule-set for 3.5 as well. I don't have the link for it, just a Word Doc. I can send it over if you want.
This looks awesome... I'll have to give this I shot. I will shoot you over a PM if I end up needing the 3.5 conversion for it. Thanks!

[Lerondiel]

If you're not familiar with the Red Hand of Doom module, one of its last scenes is defence of a city, broken into encounters with the victory point concept. The Miniatures Handbook also has a lot of advice for DMs wanting to make a battle on a larger scale but still keep it manageable and have the PCs at the right level of relevance.