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Dr paradox
2018-07-15, 02:12 PM
Alright, so I'm running a mid-level 5e game (The system's not especially important) in a fairly low-magic medieval fantasy setting, and in the next couple of sessions the players are going to be commanding their collective forces in a defense against an undead horde.

My players aren't especially interested in wargaming it out, but I'd still like to include enough choices and decision-making to make it more than a string of battles atop the castle wall. I might make it a series of branching paths (i.e. Ride to the gatehouse to support the guards against the skeletons climbing the portcullis or take out the zombie wyverns buzzing the south wall) but my players have a nasty habit of splitting up anytime a halfway difficult choice comes up.

They all agree, splitting the party is bad tactically, it makes it now fun for whichever group isn't currently the focus, and it slows the game to a crawl, but every time a time-sensitive choice comes up, they split the party anyway. I had to give them a serious hairy eyeball to keep them from splitting their group across two entirely different quests a few months ago. I love 'em, and it probably speaks to a greater investment in the outcome of the story, but YEEZUS.

Anyway, I'm thinking that I can mitigate this by designing a system for troop deployment. They get a deck of cards representing certain units they've obtained over the campaign, like "General Stanikov's Veteran Division" and "Sashka the Blue's Colleagues" that they can send to deal with whatever problems they don't go after personally. I figure these can be defined simply by three stats: Might, Magic, and Discipline, to cover their abilities to counter specific kinds of threats.

What I'm interested in is ideas for how these mounting threats can be defined and played out. Something like checks and DCs? How do troops get diminished, or destroyed entirely? Should I shoot for a bell curve distribution to go with the way the performance of a hundred men is more predictable than the performance of one man, or should I stick with a linear distribution to keep the tension high?

TheYell
2018-07-15, 02:35 PM
Um, did you just ask us to create a wargame for you?

Simple way to do it is, units don't get destroyed, they just have a competing roll on one of the three stats determined by the attacker, somebody wins, somebody loses, loser retreats.

Dr paradox
2018-07-15, 03:03 PM
Um, did you just ask us to create a wargame for you?


Nnno, sorry, I guess I was unclear. I'm trying to figure out something quick and dirty, not too involved and pretty easy to resolve between actual fights. The extent of the decision-making should be deciding which troops go where.

Here's what I've mulled over in the last 20 minutes. Challenges such as Wyverns buzzing the walls and undead Aurochs battering the gate aren't units like the troops the players control, they're more like set difficulty classes or skill challenges, where every round the units engaged make a check described as 3d6+Might. A success clears that particular peril, a failure reduces the relevant stat of the unit and calls for another check on the following round.

For example, a Witchfinder Brigade (Might +5, Magic +3, Discipline +3) is dealing with a siege tower full of Wights approaching the wall (Magic DC 14 to destroy the tower before it reaches the walls.)

They roll 3d6 + 3, and get 12. Their magic is reduced by one to account for wasted spells, and the next engagement comes around.

Now the siege tower has arrived at the walls, and it's turned into a pitched melee (Might DC 15 to defeat them)

They roll 3d6 + 5, and get 14. The wights are too numerous, and they take losses represented by a rediction of one might.

The heroes notice the battle on the walls, and send a division of Peasant Levees (Might +2, Magic +0, Discipline +1) to assist.

The Peasants roll 3d6 + 2, and get 12. They take losses, but aren't defeated.

The Witchfinders roll 3d6 + 4, and get 15. After some losses, they manage to dispatch the last of the Wights and clear the wall. Both they and the peasant levees are now free to be redeployed.

Coretex
2018-07-18, 09:44 PM
No offense, but I think this is the wrong way to go about your stated goal of making the strategy the primary challenge.

Setting skill challenges around the place lead to a best case scenario of:
The right characters take on the right challenges for them, beat back the enemies with a few rolls.
A worst case scenario of the opposite, and a far more likely middle ground where nothing feels really impactful and drama is minimal.

I would suggest instead something far more abstracted. The fun comes from letting characters do things that suit them in ways that contribute, so make options for that and then stat out for maximum satisfaction.
Fill the castle (or allow them to fill, depending on where this is at) with options for defense and breaches and let the characters take positions amongst them where they will.
For example:
A tower with a large ballista and a small crew to man it. A player might decide to lead that crew, taking shots at things that present as a risk every round.
A large gatehouse where the enemy tries various things to break in: rams, ladders, chopping at the gate, etc. A player might decide to lead the defense of this, taking control of the entire guard here. They have to think of ways to overcome the various attacks, which will probably include help from their friends in the other areas.
Various sections of wall, under attack from siege towers, ladders, flying sweeps against the defenders, etc. A player at any point on the wall bolsters the defenders and can lead the defense there.
A sewer entrance for surprise (or maybe the champions were prepared so a satisfying failure of an) attack.
Any other physical features. Plus, various types of defending troops.
Maybe there is a troop of archers stationed in the bailey. A group of knights on horseback who can sally out (ride out at opportune moments to destroy key equipment/troops, but will perish if bogged down out there). A squad of engineers who can build things mid fight (very fast, to keep it interesting).


Then you draw out a simplified map (not the one you show to the players) that has each area separated by one turn (whether that be the usual 6 seconds or more). Put enough areas that no more than 50% of them can have a player present at a time (this is crucial to the difficulty of the siege, you can make it easier or harder depending on how thinly you stretch them). Make a table with each area having it's own column and track where players start and the status of each area. Every row is a turn.
Half done! The hard part!


Once you have that it is really easy to visualize what you need to do to make a challenge for each turn. Areas without players have a chance to falter in their absence (a simple 1d20 + special details modifier (like spike pits + 2, boiling oil + 5, Player + 5 for defense; Ladders + 1, Ram + 5, Tower + 10, swarm + 3, for attack) for each side. To determine how the battle rages there). Areas with players are where you focus your attention and just make sure that there are things demanding their efforts. A siege tower should have enough hp that it is a threat and an investment for the defenders to drop, a ram should take some special thinking to destroy, a rush with ladders can take some good rolls from the defenders. Drop these obstacles into the table down the rows to keep the pressure on and give you an idea of what you need to warn them about each turn.

Then you narrate through the various areas from a sky-high perspective.
"The rear walls are holding back their assailants after that fantastic rally by Joe as he rushed to defend the southern bailey. Rumbling up from towards the eastern wall you see the Siege tower get slowly closer, even as it wobbles uncertainly where the ballista tore large holes in it's side. The knights in the northern bailey steady their horses, waiting for an opportunity to fight for the castle. Down below, you hear screams as something stumbles into the traps that were placed there. The gate house is nearly swamped with undead, crawling up the ladders and the fighting on top is tense. Around 100 yards away you see a ram making it's way towards the gatehouse, determined to break down the large wooden doors. What do you do?"

If you have your table set out it's really easy to run through and dramatize it all for maximum enjoyment of the players. I ran through something like this very recently and as always it comes down to getting them engaged and knowing that their actions are powerful. If someone throws a fireball into a mob, let the mob die. Mark on the table for that area as charred and largely empty for one turn and move on.

I could think about this all day, but you get the idea. The more options the better, and the only numbers you need are modifiers to the combatants in each area (you can make them up on the fly from what is there) Plus the hp of the various major players.
Just make sure to weigh those numbers towards the attackers so that players make the swing most of the time wherever they are.

I hope this helps. Try making that table really quickly (adjacent areas at top, time on the side) and see if it doesn't spur you to fill it with interesting attacks on the various sides.


*Edit:

Oh, and for when an area gets overrun: They lost the last rolls and no reinforcements came, they roll one more time without their modifiers. If they lose, the area is taken and it changes the battlefield again. This should happen! The heroes can be too busy to defend everywhere that needs it (or they might stuff up) but then they can retake it, potentially at other cost.

Florian
2018-07-19, 02:35 AM
Hm. Are you willing to convert some Pathfinder sub-systems? The Ironing Invasion campaign uses a modified version of the Downtime Rules to manage a guerrilla army, with a focus on deploying teams to handle tasks like scouting, securing the perimeter and such.

zlefin
2018-07-19, 08:08 AM
dunno whether it'd fit,
but you could adapt something from pathfinder's mass combat rules

or if you have access to it the legend of the 5 rings rpg books have some rules for how the players affect large battles that might be of use. (at least 4th ed does iirc)

Dr paradox
2018-07-19, 01:43 PM
Snip

All really interesting stuff, and I'll probably steal an element or two of that - most prominently the adjusted DCs based on the defenses. of a given area.

My main concern is, that approach all but demands they split the party, and fall into a loose, semi-improvisitory mode of castle defense. I want the bulk of the time to be spent in tactical combat mode - initiative, rounds, roll-to-hit, the usual D&D, but I want it to be contextualized within a FRAME of a larger battle with objective stakes. They decide whether to deal with the approaching siege tower, the undead dragon scouring the artillery tower, or the pack of ghouls the dragon just dropped off in the Lower Bailey. They then go off and have that fight, leaving their troops to deal with the remaining problems.

Those troops, also, are something I want to specifically look in on. Three of the players have their own cadre of followers (A mercenary company, a gaggle of beleaguered apprentices, and a brigade of crack witch-hunters) and one of them is a feudal lord who can bring their own forces to bear. Additionally, they've been making allies and buying up more mercenaries over the course of the campaign. As a result, I feel the need to make it more about the units and characters than about the castle, since the NPCs are the thing the players have any investment in.

I've done a couple rounds of playtesting, and here's what I've got so far

For one, they're not commanding ALL the troops. It's assumed that the Castellan has deployed the bulk of their forces around the castle competently. The heroes just have the elite troops in reserve in the Bailey, to be dispatched to offer reinforcements when an area is threatened to be overrun.

They can dispatch any number of these reserve units to deal with a problem. They add their respective bonuses to one another, and roll 2d10 (It's a little swingier and more fun to roll than 3d6).

On a success, they turn back the invaders with negligible loss of life. On a failure, they still turn back the opposing forces, but at great cost to themselves. They become "Beleaguered." If a Beleaguered unit fails a roll, it is overrun and destroyed. If all the units attempting to throw back the enemy are destroyed, then that spot on the battlefield is lost to the enemy. Players can choose not to send reserve troops to deal with a crisis, which cedes that part of the castle, but also results in no losses.

The DCs of particular enemy forces are modified by whichever portion of the battlefield they're trying to gain. It's easier to take the Lower Bailey than the curtain wall, for example, and enemy progression is divided up into "lanes" of approach. These run, for example, North Wall - Lower Bailey - Upper Bailey - Keep, or Gatehouse - Upper Bailey - Keep, or Cliffside Wall - Keep. If the Keep is taken, the battle is lost. If multiple crises have progressed through their lanes to the same location, the units in that spot have to roll against them each in turn.

I keep track of all the DC adjustments and lane progressions behind the screen - all the players need to worry about is reserve deployment.

Having run two playtests of this, I'm pretty pleased so far. I've been charting out the course of the battle as if the heroes weren't there, and in both cases the defenders wound up having to cede territory to deal with more pressing concerns, then were overwhelmed and slaughtered to a man. Next I'll try testing with simulated heroes - essentially one "freebie" per engagement. Past that, it's mostly fine-tuning the DCs and bonuses.

The Jack
2018-07-19, 04:20 PM
Climbing the portcullis?

If you're doing low magic, I suggest a castle that's not so big. Actually, it's smarter to make a castle small for a fair few reasons. The defensive design philosophy of the medieval castle is that you get the most out of only a few defenders. If the castle is very spread out, you'll need more people to defend more land, which means not only do you have more mouths to feed, but you can't leave a small garrison and send out a big army, you've got to leave far more soldiers and thus weaken the army you've sent out.


Next, even when the castle is big, they're designed to have few viable ways to attack and plenty of redundancies on the way to the keep. When designing a bigger castle you'll want layers of defence but you'll also want to funnel opponents into killzones. Every gatehouse is a slaughterhouse, every path is below archers and folks with rocks, and bonus points if the enemy have to climb narrow starcases while being shot at.

I recently visited castle Trakai. the attack process would be something like
Cross a narrow (removable) bridge to the island it's on (or use boats) while being shot at.
Go through a gatehouse
Fight through a courtyard surrounded by mighty towers.
Go across a narrow bridge, and get through another gate. It's time for the actual castle (the defenders could elect not to defend everything before now if they were short on people)
You're now between walls and the keep, get into the keep; It's time for another gatehouse.
Once you're through the gatehouse, you're surrounded by the building, not actually indoors yet, and there are three floors for you to climb whilst you're surrounded.

Climbing the walls... doable for the optional part, difficult for the "real" castle's outer walls, but you're not climbing the walls of the keep, no way, and in a fantasy setting you're not likely to have a good time trying to get wyverns in it, it'd be a deathtrap for them too.


Now, most castles are less than this. Like, a keep is basically all there is to most castles, maybe with outer walls and a single gatehouse if someone was rich, but the keep? There's no tactical thought needed. Put a couple of folk on the roof and the rest'll surround the bottleneck murderzone that is the door. The enemy has no choice, the defenders have everything planned.


Trying to climb the wall whilst it's well manned is crazy. There's death from above, death from the sides, and when you get to the top you're at a huge disadvantage because the defenders have good cover or better and you have "disadvantage" from fighting on a ladder (plus other disadvantages, like needing to keep a hand free to climb and thus being a little less armed, getting to the top to be outnumbered and flanked, being tired from the climb, the terror which admittedly isn't really a thing with undead.

A lot of thought goes into making castles an absolute mother****er to attack. That's why people did the boring and tried to starve people out most of the time.

Beleriphon
2018-07-19, 04:47 PM
Trying to climb the wall whilst it's well manned is crazy. There's death from above, death from the sides, and when you get to the top you're at a huge disadvantage because the defenders have good cover or better and you have "disadvantage" from fighting on a ladder (plus other disadvantages, like needing to keep a hand free to climb and thus being a little less armed, getting to the top to be outnumbered and flanked, being tired from the climb, the terror which admittedly isn't really a thing with undead.

A lot of thought goes into making castles an absolute mother****er to attack. That's why people did the boring and tried to starve people out most of the time.

Mind you its different when the horde attacking is an unbreakable wall of undead that only stop when the last of them are destroyed. Oh,

Still, if one wants to go with a "traditional" medieval castle it helps to know what kind of castle it is, what is meant to do, and where its built. A castle build on a flat plain with no height advantage is a siege waiting to happen (and stupid). A castle built on top of a ridge line with a single path up to it is an observation point, and defensive position. A castle build near a river has a source of water, and probably only needs to functionally defend one side of its facing.

Now the purpose of the castle: is it a fortified home?; is it a fortress meant to defend a region?; a fortified way point meant to protect travelers? Knowing that will help in designing defenses, a home will have escape routes and probably have large keep to house a family in some comfort. A fortress is a military camp, comfort isn't high on the list of things it is supposed to be. A waypoint will have space for traveler to pitch tents, resupply, stable horses, and probably have a relatively small number of permanent residents.

Dr paradox
2018-07-19, 07:26 PM
The Castle is, specifically, a military fort in the foothills of a vast mountain range, meant to be a watch-post for hobgoblins most of the time, but suitable as a staging ground for massed offensives against said goblins when necessary. It's perched on a high overlook, with a chasm to the east and sloped gullies and cliffs on the north and west. The gatehouse is on the south wall, accessible only by a narrow road that winds under the southern wall and western tower. As of now, the castle is being used as a staging ground for preparations to go after a necromancer whose set up shop deeper in the mountains, and they're awaiting reinforcements from the capital.

The necromancer has decided that he ought to try and take the castle before these reinforcements arrive. Without said castle, the arriving army won't have a point of defense to rely on, and will be much more vulnerable on the march to his tower, hence an assault rather than a siege.

Finally, I thought the castle ought to be large enough to contain all the currently assembled forces, otherwise it'd have to wind up as a much more sprawling and complicated battle across the surrounding rough terrain, and necessitate that they take catastrophic losses before they even get to the cool bit of battling skeletons on the parapets.

Overall, the tone is an "end of the second act" affair.

Coretex
2018-07-19, 08:08 PM
My main concern is, that approach all but demands they split the party, and fall into a loose, semi-improvisitory mode of castle defense. I want the bulk of the time to be spent in tactical combat mode - initiative, rounds, roll-to-hit, the usual D&D, but I want it to be contextualized within a FRAME of a larger battle with objective stakes. They decide whether to deal with the approaching siege tower, the undead dragon scouring the artillery tower, or the pack of ghouls the dragon just dropped off in the Lower Bailey. They then go off and have that fight, leaving their troops to deal with the remaining problems.

True about splitting the party. Its a different style of defense to what you have described next where they fight various parts as a party. I don't know if the two styles (which your next statements describe you as wanting) really mesh very well. Ill explain in a sec.



Those troops, also, are something I want to specifically look in on. Three of the players have their own cadre of followers (A mercenary company, a gaggle of beleaguered apprentices, and a brigade of crack witch-hunters) and one of them is a feudal lord who can bring their own forces to bear. Additionally, they've been making allies and buying up more mercenaries over the course of the campaign. As a result, I feel the need to make it more about the units and characters than about the castle, since the NPCs are the thing the players have any investment in.

That's cool stuff, and should totally come into play. But again, doesn't match either the afore-mentioned squad fighting nor the next mentioned tactical defense.



For one, they're not commanding ALL the troops. It's assumed that the Castellan has deployed the bulk of their forces around the castle competently. The heroes just have the elite troops in reserve in the Bailey, to be dispatched to offer reinforcements when an area is threatened to be overrun.

They can dispatch any number of these reserve units to deal with a problem. They add their respective bonuses to one another, and roll 2d10 (It's a little swingier and more fun to roll than 3d6).

and the rest...

So judging by these quotes we have 2 different styles of combat at play.
1: Typical D&D squad-fighting within the framework of a castle under siege, where the players determined some of the defensive capabilities before hand and their squad will have to defend wherever they neglected.
2: A top down tactical defense of a castle. With interesting decisions about bolstering defenses or ceding territory while their own troops run around hither and thither.


I think I get what you are trying to go for here, but I am not sure it will play out like you imagine it.

You can easily make option 1 work and be fun by starting with them deploying their troops (they count as a defense auto-win in this style) and then essentially staging everything. Make a timeline of interesting things happening, with various places losing ground/being destroyed for the purpose of giving the heroes interesting choices often. Essentially, instead of using the table I described earlier, build a branching tree and let them decide which branch to take at every point. The other side probably loses (or maybe succeeds) based on your design. Don't get stuck too heavily on rolling for everything this way. This is a theme park where the ride is their combat with the enemy squads. They can choose to go down different routes but the framework is designed for maximum drama and giving them fun options. If rolling could result in all of the walls being fine or all of them being destroyed, your squad fight will be ruined by "and then infinite undead swarm your position through no fault of your own" or the opposite.

Their troops should definitely come into play. But for the heroes to have any real impact in the fight either the individual fights have to be smaller (eg, a team of apprentice necromancers drop onto the artillery tower and start raising nearby troops on the inside) or the heroes have to operate on a larger scale (my suggestion of having them rally nearby troops and determine the defense wherever they go. Also, I'd suggest buffing spells be allowed to have a less powerful affect on a whole troop (bless gives a +1 to the defense here, instead of rolling for everything or making it worthless))

Option 2 is essentially what I was describing in my first post. It can be a lot of fun and the addition of their private squads would both up the personal connection ante and the danger due to their probably propensity to withdraw their army for fear of losing it.

I know you want them to fight as typical D&D style, but in this kind of combat you run into all sorts of problems with timescale and physical space. For anything interesting to happen while they fight you need a timescale of 6 seconds - 12. So that every round or two you can update them on the state of the battle at large. But running around a castle takes ages, and moving between fights to handle problem areas will take ages unless it is carefully crafted (see option 1). Also, without them fighting on the highest tower all of the time their vantage point would be severely limited. What you will be able to describe is limited to the wall above them and the screams from the other side of the castle.

I would personally abandon Party-wide typical rolling for the Siege (at least until the end where they face various leaders/the boss). A few players on a particular spot will roll for their attacks as normal, but with the scale here we are talking: "you (rolled over the ac for this foe type) hit, roll damage... with a mighty swing you cleave 4 of the zombies in half."
Essentially, the siege is a big combat. The players choose the ac for the various defensive points and the enemy chooses what abilities it uses to try to break them. The players use resources to defend the points and each of them positions themselves around the fight where they will be most useful/have the most fun.

The party is likely to stick together in some portions, and separate in others, which really just lets each character be most useful (and feel the tension from mistakes/losses) where they want to be. Just like an archer hanging at the back of a combat, one player might hang back. Roll through that for the rest.

This is a bit more complicated than option 1, but IMO more fun (and certainly special and memorable).

Beleriphon
2018-07-19, 09:32 PM
Interesting stuff. For actual mechanics its going to depend. D&D characters are best suited a doing something like hacking their way through the horde of zombies and then having an epic battle with leader of the horde. The game is predicated on that being what you will be doing. So to no small degree any kind of castle defense mini-game is going to run up against the way normal D&D combat works.

I'd go with some set piece battles, with success or failure (failure be defined as too many gribblies run past the party, as opposed to death of all PCs) determining the end of the battle. I'd tally it up using victory points. With points determining different levels of success. So they get all possible points, its a minimum of life lost for the defenders and most if not all of the horde is destroyed. Some lesser value, go with success but more deaths, and half the horde retreats, and thus down the scale. This gives the PCs a bit more direct control of the outcome based on their heroic actions, rather than trying to get them to mini-game the battle which could take hours and hours, rather than the quick and dirty one minute melees D&D tends to run on.

Avigor
2018-07-22, 04:21 AM
Whatever you do, never for the MACHICOLAAAAATIOOOOONNNNNNNNSSSSSSSSS! lol I love Shadiversity, you should probably watch some of his castle videos.