D&D 5E How do you prep/run stealth missions?

[Quickleaf]

Come next weekend's game, my 10th level party* intends to assassinate the evil Lizard Emperor in his forward operating base within the jungle. They know it's full of lizardfolk warriors and dinosaurs, and that his mage advisor Nataxl is actually a night hag in disguise. The night hag is a secondary target, either for assassination or subduing and forcing to craft a particular magic item for the PCs.

During this week, they're devising their plan while I'm trying to prepare. Obviously, I want to include all the PCs without it being reduced to a bunch of Dexterity (Stealth) checks to see if they gain surprise or are noticed. I've attached the map I'm using for the Lizard Emperor's camp.

What are the best ways to prepare and run a sneaky assassination mission?

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The party includes:

• Lizardfolk Rogue 6 (swashbuckler)/Warlock 4 (raven queen) who's stealthy as hell, has a special bird companion, and has magic items aiding in disguise
• Grung Druid 10 (circle of the land) with the Hand of Vecna and making good use of pass without trace
• Goblin Paladin 9 (oathbreaker)/Sorcerer 1 (wild magic) who is good with undead and has a small squad of goblin allies
• Human Wizard 7 (divination)/Rogue 3 (mastermind) with an owl familiar, a crystal ball, and excellent at divination-based recon
• NPC Artus Cimber, an archer wielding the powerful Ring of Winter

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Some notes I've made so far...

• Players will want to recon the heck out of the forward base. I'll need a bunch of detail, but I'm concerned my players will go overboard here (I've seen them do it before) and then there's less time for executing the plan, and the rest of the session can feel rushed. So maybe I can come up with some kind of recon check which determines how much recon they can get through magic/familiars/scouting before realizing they're pushing too much and risk getting discovered if they try any more...
• What if getting noticed is like the "click" of a trap, and then the player gets to react? For instance, the guard might only have noticed an unusual shadow or heard something or be about to turn their head. So the players get a reaction to save themselves, if they think fast.
• Creating opportunities to hide should be important – extinguishing lights, distracting patrols, controlling weather, taking down and replacing a key sentry, etc. Successfully create the opportunity to hide? OK, you're hidden, no need to roll dice.
• Stealth checks should be an option of last resort – if you need to make a Stealth check something has gone wrong and you're at immediate risk of discovery / the alarm being raised.
• Though perhaps an initial group Stealth check (averaged) determine how close to the heart of the forward base the PCs get without being spotted. So perhaps I design 3 concentric rings of security – the outer camp (DC 10), the mid-camp (DC 20), and the inner camp (DC 30) – and their group Stealth check (averaged) determines how many they bypass. Though based on their Stealth scores and pass without trace it's pretty clear that an averaged result would be the mid-camp.
• Because my party has scry + teleport tactics at their disposal, think of some advanced defenses vs. magical infiltration. Line of sight to the center of the base might be limited to prevent teleporting in. A lantern of revealing being used to scan for invisible creatures or scrying sensors (though its range sucks).
• Make a random table with snippets of conversation – some humorous and some useful – for PCs to overhear. Stealth-based video games seem to do this well. And every time I've seen a player running a sneaking PC who comes across unaware enemies, they always want to eavesdrop.
• Reinterpret Inspiration as a flashback mechanism to allow a player to say "Aha! But I remember when I…" and then describe some bit of planning their PC did that the players never actually planned for. This is borrowed from the Leverage RPG, but I really like it for D&D where plans rarely seem to survive actual play.
• Think up several complications/twists, around one per PC, which I can spring to keep the players on their toes or use when something goes dramatically wrong.

 

[iserith]

I would just do a set amount of specific challenges, perhaps 2 per PC (excluding NPC), that make sense for the adventure location and all point toward infiltration mechanically.

For any given challenge, at worst the PCs get progress combined with a setback on a failure until they've accrued a set number of failures (perhaps half the total number of challenges?) at which point the jig is up and they fail to achieve their ultimate goal, whatever that means in context.

The better able you're able to insert challenges in where they make sense (rather than follow a linear script), the better, so I recommend more abstracted ideas you can fit into the situation as it unfolds. To that end, just making a list of "infiltration complications" would be the way to go in my view.

 

[Quickleaf]

I would just do a set amount of specific challenges, perhaps 2 per PC (excluding NPC), that make sense for the adventure location and all point toward infiltration mechanically.

For any given challenge, at worst the PCs get progress combined with a setback on a failure until they've accrued a set number of failures (perhaps half the total number of challenges?) at which point the jig is up and they fail to achieve their ultimate goal, whatever that means in context.

The better able you're able to insert challenges in where they make sense (rather than follow a linear script), the better, so I recommend more abstracted ideas you can fit into the situation as it unfolds. To that end, just making a list of "infiltration complications" would be the way to go in my view.

Thanks iserith. So sounds like you're alluding to a sort of skill challenge approach with "Schroedinger's complications"?

How were you imagining success/failure playing out at the individual challenge level vs. the overall mission?

 

[Tony Vargas]

Obviously, I want to include all the PCs without it being reduced to a bunch of Dexterity (Stealth) checks to see if they gain surprise or are noticed.

Minor thing you probably already know: if you do go with stealth checks at some point, do a group check. IIRC, they're still in 5e, and they provide a reasonable chance of a mixed group of highly/semi-/un- skilled characters actually succeeding at, well, something.
(ah, I see you're already planning on that)

also a good idea:

Reinterpret Inspiration as a flashback mechanism to allow a player to say "Aha! But I remember when I…" and then describe some bit of planning their PC did that the players never actually planned for. This is borrowed from the Leverage RPG, but I really like it for D&D where plans rarely seem to survive actual play.

Because my party has scry + teleport tactics at their disposal, think of some advanced defenses vs. magical infiltration. Line of sight to the center of the base might be limited to prevent teleporting in. A lantern of revealing being used to scan for invisible creatures or scrying sensors (though its range sucks).

I suppose you could assume that hag has set some stuff up, assuming non-combat magical abilities not in her stat block, perhaps. Maybe, if she has any reason to suspect the caliber of opposition coming for them, she could have a deal with a night hag to screw with scrying/divination, invade dreams of resting casters trying to recover spells, or other dirty hag tricks.
There's also all the classic ghetto tricks to foil invisibilty et al. The lizardfolk are likely comfortable on swampy ground, anyway, so choosing soft ground for their camp will also make it hard for anyone to approach without leaving very obvious footprints, they can incorporate bogs/quicksand and the like into their defenses, keep animals with keen hearing & smell and pay attention to them, etc...

 

[Salthorae]

I would do a skill challenge (one of the things from 4e that I actually appreciated!).

Here's a good reference also a good video from Matt Coleville on running Skill Challenges

Reddit examples/notes 1 notes 2

 

[iserith]

Thanks iserith. So sounds like you're alluding to a sort of skill challenge approach with "Schroedinger's complications"?

I hesitate to call it a "skill challenge" because that comes with a lot of baggage. Here I propose just a series of obstacles to overcome which may or may not call for an ability check, depending on what the players decide to do about the obstacles. Adjudicate like any other action per the rules, but make the failure state always be progress combined with a setback instead of "you failed so now they're onto you."

How were you imagining success/failure playing out at the individual challenge level vs. the overall mission?

Without getting into specifics as to your scenario, basically any given obstacle cannot trigger a failure for the overall challenge. It's the accumulation of failure that snowballs into an undesirable result. A failed attempt to overcome an obstacle might instead be "success, but the next obstacle is harder" or "success, but it costs you some resources."

 

[Bacon Bits]

In my experience, infiltration types of missions are not difficult to prep for as long as all you do is what the NPCs themselves actually have to do. That is to say, set up rough schedules of what the guards will be doing, what countermeasures the NPCs will have, and what the numbers of reserves look like and what happens when the alarm is sounded. Then you treat the entire mission as one block of XP.

Simply put, trying to force encounters to go a certain way with stealth and infiltration will just often not work because the my players almost never do things the way that you think they will. They will come up with multiple ideas that you never even considered so you won't have any plans to address. One of them will have disguise or illusion magic and walk right past your guards. Or they'll use charm magic to make friends out of enemies long enough to get what they want. Or they'll split up with one party causing a distraction while the others get what they're looking for. Or they'll have a timed distraction. Or they'll make a coordinated strike and hit fast and hard.

Don't think about what the party can do, per se. Think about what kinds of things the NPCs would be interested or could feasibly stop. Sure, the PCs can teleport and use scrying. Do the NPCs actually have secrets that could be scryed? Do they have other enemies that are known to teleport? How paranoid are the NPCs What kinds of threats do they already routinely face? What simple things can they do? Do they have perpetual light spells? Alarm spells? Arcane lock? Glyph of warding? Guards and wards? Symbol? Forbiddance? Note that many aburation spells are rituals. What kind of escape plan do the NPC leaders have? What do they care about the most? Who do the NPCs know that would sell or give them resources?

This kind of prep is when the DM gets to roleplay. You get to think like the NPCs and make plans and formulate them. Use your resources as best you can, and don't pull punches if the PCs walk into your preparations (but do have potential backups in mind if the PCs suddenly can't succeed). IMO, don't think so much about challenging the players as much as you are thinking about playing the NPCs correctly. You can always adjust the latter to fit what the former requires.

 

[Quickleaf]

Minor thing you probably already know: if you do go with stealth checks at some point, do a group check. IIRC, they're still in 5e, and they provide a reasonable chance of a mixed group of highly/semi-/un- skilled characters actually succeeding at, well, something.
(ah, I see you're already planning on that)

Thanks Tony.

Yes, I know it seems like a deceptively simple question. Stealth mission? Make a group Stealth check! But I've seen stealth-based missions go wrong often enough to want to head off common errors at the pass, and instead make this something that engages all the players, builds tension, respects their planning but encourages them thinking on their feet, and with multiple possible outcomes for how the assassination goes down.

Also, at a certain point rolling a Stealth check, as a group check or otherwise, is not really satisfying. We know who the high Stealth characters are, we know that with pass without trace they can get numbers that will eclipse most opposition, so barring exceptionally bad rolls or ridiculously high monster's passive Perceptions they're going to succeed a group Stealth check.

So my idea to have them roll a group Stealth check up front to see how many "concentric rings of defense" they bypass is meant to do a couple things:
1. It scratches the player's itch/expectation to roll for Stealth. Psychologically, it sets the stage that you've already rolled Stealth...and now the adventure begins. Hopefully, this will be enough to counter my players' tendency to reach for dice when they say they want to sneak past a sentry.
2. It fast forwards past (some) defenses that my very detail-oriented players could easily get lost in countering, performing reconnaissance of, or otherwise mucking with.
3. It establishes that they're working together and this is not a scenario where the lone wolf – in our case, the lizardfolk rogue PC – is going off on his own.

I suppose you could assume that hag has set some stuff up, assuming non-combat magical abilities not in her stat block, perhaps. Maybe, if she has any reason to suspect the caliber of opposition coming for them, she could have a deal with a night hag to screw with scrying/divination, invade dreams of resting casters trying to recover spells, or other dirty hag tricks.

She is a night hag, currently disguised as a lizardfolk mage. She does know about the PCs and that they're dangerous, but she has other matters occupying her attention, like further insinuating her way into the Lizard Emperor's court & trying to find a magical shadow that she bound but has since escaped.

I've established that this night hag made pacts with goblins, turning them into redcaps. The theme I've got for her is "grotesque alchemist" who promises to make creatures better, stronger, more beautiful, or whatever with her brews, but her foul transformations only lead to tragedy.

There's also all the classic ghetto tricks to foil invisibilty et al. The lizardfolk are likely comfortable on swampy ground, anyway, so choosing soft ground for their camp will also make it hard for anyone to approach without leaving very obvious footprints, they can incorporate bogs/quicksand and the like into their defenses, keep animals with keen hearing & smell and pay attention to them, etc...

Yes, the camp is set up near water. The 10th level party does have magical flight capabilities, though at some point they will probably land (based on past stealthing) to approach on foot and avoid being spotted.

Footprints is an interesting point that usually doesn't come up when sneaking. Chances are the party will have pass without trace going, so it becomes a moot point.

The enemy lizardfolk have blood hawks (reskinned as archaeopteryx) which have Keen Sight.

 

[Beleriphon]

I think what you want to do is look at the ultimate goal, and then place reasonable challenges in the way that make it seem stealthy, without having to use said mechanics.

For example, can the group draw a patrol off to create a hole in route long enough to do what they need? So if the patrol comes by a point every hour, then if they can get that patrol out of the picture then now they have a two hour window before anybody notices.

As a thought, getting to the Lizard Emperor probably shouldn't be hard, its the getting out alive that presents the problem. Lets pretend for a second they get into the camp, kill the Emperor, I'm assuming that isn't going to be quiet given the presence of a night hag. So, now we have a bunch of middling level PCs surrounded on all possible sides by enemies. How do they out is often more important than how to get in.

 

[Tony Vargas]

She is a night hag, currently disguised as a lizardfolk mage. She does know about the PCs and that they're dangerous, but she has other matters occupying her attention, like further insinuating her way into the Lizard Emperor's court & trying to find a magical shadow that she bound but has since escaped.

I've established that this night hag made pacts with goblins, turning them into redcaps. The theme I've got for her is "grotesque alchemist" who promises to make creatures better, stronger, more beautiful, or whatever with her brews, but her foul transformations only lead to tragedy.

That is just made of awesome.

She needs to find some way to get the PCs to find the shadow for her (like play out a scene when she notices they're scrying that makes them think it's in their best interest or something).

If the players /have/ figured out what she is, it'd be amusing for her to substitute a fake or actual lizardfolk mage for herself at an opportune moment. Challenge them to 'dispel her disguise!'