Hello All,
Was wondering if any of you have ever run or played in a “City or Castle Under Siege” adventure in the Realms?
If so, were the attackers the typical orc/goblin hoard? Or something different, like undead or magical beasts? Did you have fun? What parts did you like the most/hate the most/not care for? What do you feel could have been done differently?
And even if you haven’t played in a scenario like this, do you have any thoughts or ideas on how you’d run it if you were the DM?
I’m wrapping up my 3.5 campaign and want to tie it off with a siege of a castle the PCs are in, where swarms of fast-moving undead (like the zombies in the movie 28 Days Later) attack from all sides and come up through the castle cellars, so I’m looking for any campaign advice I can get.
I want to scare the pants off my players and leave them with a “we survived by a hair” feeling.
The adventure would start with the players sneaking into the castle; for whatever reason. Could already be filled with hostiles, might need to steal something from the keep, whatever. Sometime around when "Reason for Coming to the Castle" is done, the castle comes under siege. I'd probably try to make it look like the PCs helped with the siege (if they sneaked in, it's possible that they could have been followed in), when in truth, those who sieged the castle would be enemies of the PCs.
@Timmeh: I’ve been borrowing themes and ideas for encounters from the movie adaption of The Name of the Rose, so the PCs have been dealing with unexpected murder and intrigue in the keep proper, while attending to their original task (given to them by the Regent’s Lord of Tyrluk): exploring a (formerly sealed off) dungeon complex beneath the keep to try and find a missing noblewoman (Lady Immerdusk) of Cormyr.
My idea was to flip things towards the end: the PC’s rescue of the noblewoman unintentionally causes the release of a potent magical plague; one that infects vermin (rats mostly) and drives them to seek out the dead and feed on them (which turns the corpses into ravenous undead).
The keep sits on a hill, steep on three sides while the fourth side (the front face of the hill) has a hard packed road. On either side of that road are buried several centuries worth of sages and worshipers of Helm and Oghma. This will be my undead army to swarm Sagekeep. 
Timmeh, I think I’m going to take your idea and modify it so the NPCs in the castle come to believe the PCs are directly responsible for unleashing the plague. This way the PCs have a shot at roleplaying and diplomacy to try and unify the keep’s denizens before things get really bad.
Thank you for suggesting it!
@Stigger: the theme I’m going for during play of the siege is one of being overwhelmed and overrun, with a side of dwindling resources and no chance to rest. Enemies from all sides, players running out of spells, NPC allies dying and being animated/turned against you, nowhere to run.
I don’t want to TPK the party, but I do want them to feel doomed.
I’m just not sure how to give them their slim hope…something for them to latch on to and make an all out effort for. The zombies will be very vulnerable to fire (fun in a keep filled with old, dry and brittle tomes), and there’s a Ring of Three Wishes in the topmost tower of the keep that houses the bound magical powers of the lich that resides below the keep, but I wondering about other ways the PCs can win (read: survive) beyond just going for the ring.
Maces of Disruption could turn the tide for them enough to at least break out of the trap. Maybe a scroll of something like Rope Trick to give them a chance to recuperate before making that last push to escape, while making it clear it could be their last chance, so not to waste it. Perhaps a magical armored self-propelled wagon that needs a lot of repair, forcing them to scrounge up parts for it, that might be able to roll right over the horde and get them just far enough to safety to escape before it falls apart again. Maybe, if you're feeling particularly mean, give them a small tunnel they could just fit through to escape, but they'd have to leave most of their gear behind in order to fit through it. Could be something as simple as a maul sitting near an abandoned forge that can tear through stone and earth to allow them to make their own exit at the last minute. You could do a lot of things really.
I would suggest you also to make it like Resident Evil ;) Since your PCs have a catacomb under there feet, you could create an escape route through there, maybe the old crappy sage would have seen a map in is old books. The PCs and NPCs could try to hold off the zombies, at first using oil cauldron, burning arrows and catapults, but ultimately, the zombies would find a way up the walls and then start to rampage the defending soldiers. Overwhelmed by the constant zombies, the PCs could retreat in the main castle and then the sage would come with the map. At the same moment, the Zombies would be breaking the hall on fall on the poor sage. Getting the map, the PCs and the other noble npcs would rush into the catacombs, pursued by the zombies (you may have intelligent zombies, like bosses). Finally, the PCs found the secret passage way and escape... maybe the exit could bring them to the side of a ravine (aka Indiana Jones 2)
Good luck!
For myself, I ran a few scenarios with this sort of mind. Here's what I got:
On using zombies/undead/hordes: First thing is to figure out what sort of threat they're posing and how to best use them in situations. You could do individual zombies from all sides. This, while fun, can be problem with paperwork. No one wants to keep track of 15 zombies with individual hit points round after round. So I'd suggest taking a page from 4E and using them as "Minions", meaning they all have 1 HP. This gives you the chance to throw AS MANY of them as you want at your PCs. Mage's spells seem to do great destructive work against these creatures and it'll give them the visual of blasting undead in huge swaths. It also show-cases your fighter types as they make multi-attacks against the undead and see them fall. But, they're best efforts are really put to the test as more and more and more and more of them swarm all over them.
A second alternative is to use them like a Swarm, giving them swarm traits (along with undead traits) and disease. They swarm over your PCs and attacks from your melee-based PCs seem to have little effect as it's just hacking dead flesh and bones. It gives the edge to spell-casters as they're more prone to those sorts of attacks. This is also easy on the DM for tracking hit points, effects, saves and so forth.
On using terrain/parapets/castle battlements: Basically using a castle is easy, walls always provided cover (20% miss change with ranged weapons). Archer slits in the walls provide total cover (50% chance miss with ranged weapons). Moats are often fetid pools that have disease in them, though this might not come up if your using undead. For castle offensive meaures, use Hot Oil at the entrances (dealing Xd6 fire damage depending on how hot, how much oil, area of attack... but use as a splash weapon). Also catapults can deal significant damage to areas of armies outside the walls. While I don't have the book in front of me, Heroes of Battle cover all these aspects in the campaign such as how much damage these do, area of effects, and what it takes to man them.
On "Winning" and End-Game: There are a few things you can do for these situations. The first would be to issue a Point-Based design for the PCs to aim for. These points can and should vary in danger and scenario. One could be defeat 20 zombies on the cause-way (to help the castle defenders put up resistance for the doors). A second could be to defeat the Death Knight commander and his 5 infectious ghouls (a sort of black-Ops team) that have breached the celler compartments. A third could be to hold the breach in the wall the evil Lich has blasted and fight back the horde to the moat. A fourth could be shotting down X amount of undead fliers as they bombard the castle walls with plague-infested body parts. A fifth could be to defeat the HUGE Dracolich that has landed in the courtyard and wreaking havoc amongst the defenders.
Of course, the PCs don't have to defeat ALL of these encounters, but they ALL happen and they can only be so many places at once. So you say you have to defeat 3 out of 5 or 6 of these to turn the tide. This point system allows you to keep the feel that the castle is bigger than the PCs and they're not the sole defenders of it's walls.
Another way is to make the PCs a sort of Spec-Ops group, defeating the enemy behind the lines and destroying the head monster that is facilitating the attack.
Hope that helps!!
Thank you!
Panics, the idea of forcing the party back into the dungeon in order to escape through the chasm/caverns is a great idea. I'm starting to think my players might hit on that idea anyway; regardless, the impact on play wlll be awesome, especially if the route they take lands them in the lair of the undead dragon the party inadvertently helped to create.
Diffan, I completely forgot about Heroes of Battle. That book is like six feet away from me on my bookshelf haha! Thank you for all the excellent suggestions, especially the idea of the undead dragon dropping Deadplague Zombies into the castle courtyard. That's fricking brilliant and will make a great visual for my players.