Well, that seems set up to dissolve WotC as a subsidiary.

...i prefer 5.14 and 5.24; less ambiguity...

They were nice for offline play. Selling it on spell level instead of class is a nice touch too.

Reference cards are a useful tool. I'm surprised WoTC releases them. I assume they would just invest in some dumb AI tool instead

Thank you for the disclosure that you used Generative AI.

Only two, alas.

It's either the most powerful spell or completely useless table-to-table.

Although, a little Mass Invis., and you're back on track to ninja slide-hustlin' past that guard in the latter.

edit: meant "side", but I'm leaving it.

Deep in both, if you're doing it right.

I mean, realistically, you should be using group checks instead of individual checks for stealth like this IMO

yeah came to say stealth is not invisibility.

Also worth noting, when doing group stealth, you're effectively limited by the least-stealthy party member, since it usually only takes one person getting caught to give the game away.

Yeah there's plenty of other ways to follow them, but you can't track them by prints they left.

OP is indeed a little overstated, it's a strong spell but with a very niche application, so all by all perfectly fine.

you got your fantasy in my power!

oh yeah? you got your power in my fantasy!

for overland travel when you don't want to be tracked, yes, super OP.

I mean it's a second level spell that only lasts for an hour. A dedicated tracker NPC, could still find some way to sus out where the party has gone, albeit with a disadvantage.

Now the staff of the druids or whatever that magic item is that allows for unlimited pass without trace that's almost OP for overland travel, but hey that's why the BBEG has scrying.

@juergen_hubert I don't think it's OP. With a roll for each party member, some of whom often have shit dex, and potentially a new room in the next corridor there's a good chance of revealing there's an incursion. And it doesn't prevent guards from noticing opening doors, disappearing crown jewels, or any interaction where a stealth check wouldn't be appropriate. So once discovered an action like hide is required to go back into stealth mode, just as if you didn't have the spell on you. And in a world where it exists, guards for something truly important should set up some choke point where there's just open ground and enough guards having clear line of sight to all of it.

It's almost like it encourages crazy sneaky infiltrations that would otherwise be impossible. It's almost as if it enables unbelievably fun missions. It's almost as if it makes the players feel like heroes with superhuman abilities.

Pass without a trace doesn't guarantee success. It's a bonus, but if you're walking through a field with no cover and the grass is ankle deep, sorry... no. I would have to say that only an absurdly high DC or at night still with a substantial DC would it work.

How many did they wind up with?

Note https://www.dndbeyond.com/sources/dnd/sae/players-handbook-2014#Hiding

Hiding (p. 177)

The following sentence has been added to the beginning of this section: “The DM decides when circumstances are appropriate for hiding.”

The first sentence of the second paragraph now begins, “You can’t hide from a creature that can see you clearly …”

So, for overland travel when you don't want to be tracked, yes, super OP.

For sneaking past a guard on a watch tower a couple dozen feet away and you can break line of sight or it's night? Maybe, possibly, probably.

For sneaking past a guard sitting in a chair in an empty hallway looking straight at the route you want to take? Nope, you're not even allowed to roll for it, so the bonus doesn't matter.

They were fascinated by the fork.

Or possibly disgusted. Either way is good. 😁

There were some naturally-occurring caves, but also the following:

• Some eldritch horrors sleeping in the deepest caverns beneath the city who act as a "lodestone" for evil creatures, compelling them to come here.
• An ancient cleric once attempted to build a massive vault here as a safe depository for evil artifacts. He became corrupted by them, and turned into the first Evil Overlord.
• Much later on, a second Evil Overlord appeared who wanted the secrets of the first Evil Overlord. He expanded the caves and turned them into his military headquarters for his conquering horde of monsters.
• There was also a major dwarf hold here at some point before they abandoned it.
• There is an entire drow city deep beneath the surface.
• Assorted other groups of monsters keep showing up and making themselves at home.
• Oh, and the current incarnation of the city has been built on top of this, which includes a massive sewer system that is gradually breaking down from lack of maintenance.

The whole dungeon system has developed over the course of more than 8,000 years. The general inclination of the citizens above is to wall off any entrances they find, and otherwise let adventurers deal with it. (This is another unique aspect about this city - it's the only one on the continent which has a professional class of adventurers.)

As for the Thieves' Guild, they tend to grease a lot of palms in the city watch, so they don't have to worry much from law enforcement unless they do something too blatant. However, there is a new criminal organization which is giving them a lot of trouble, and there are a lot of adventurers around, so they do have reasons to take their security seriously.

The guild have mages in their employ who could help with magical security, but none of them is present in this safe house.

Guard "dogs". Some kind of creature that fulfills the role of guard dogs, maybe trained to recognise a command word to stand down. If the players are able to scout or scry on the place beforehand they might be able to overhear one of the theives using the command. Depending on the setting you can make the creature something more interesting than just a straight combat, like something that tries to paralyze them for interrogation later, something that tries to go and alert the theives, etc.

You'll have to forgive me for my lack of familiarity of the Ptolus setting. I assume a lot of these questions can be answered in the fluff for that world, or explained by DM head canon. The following questions are what I would be asking myself about the space to help guide my design.

• What caused these tunnels to form? Erosion and dissolution, like irl caves, or something more fantastic, like the city formerly (or currently) being part of a Purple Worm's hunting grounds?
• Are there other creatures who live in the tunnels which could prove dangerous? Are they sapient or sentient? Do they hold a grudge against surface dwellers for any reason?
• Does the city attempt to manage these access points in any way? What form does that management take? Is there like a SWAT team of tunnel rats who get deployed whenever something reaches the surface, or are they proactively patrolling the tunnels to prevent incursions? Is there a records office which maintains a list sealed and unsealed entrances? How accurate is that list / how well-funded is that department?
• Does the Thieves Guild rely on greasing palms to keep their operation secret, or do they rely on the inherent danger / inaccessibility of the tunnels to operate?
• Is there a magic user within the Guild who could be responsible for setting up traps, surveillance, or alarms through magical means?
• Have members of the Guild put any effort into expanding / altering the tunnels they use most frequently? Are there capable diggers who would know how to do that well? If not, is there the possibility of a cave-in? Or, perhaps, did they contract out with the Stonecutter's Guild (for example) to ensure the work was done well? Is that an avenue for the players to get some extra information?

As far as general layout of the actual base, rather than the tunnels and subterranean access point, you mention it's in a mid-low income neighborhood, but you don't describe the building they occupy. Is it a house? A commerical venture of some kind? Does the guild attempt to keep up appearances by maintaining a cover of some kind? What sorts of apparatus would they need to keep that cover in place? If the building was originally a bakery, for example, do they continue to operate it as such? Are the employees of the front operation aware of the illicit activities they are covering up? Are they guild members, or are they civilians who are paid well enough not to ask questions?

I regret being all Socratic up in here, trying to answer your question with a series of questions, but I believe they will help you envision the requirements that a base like this would have, which will then guide what elements you need to include to achieve verisimilitude.

@juergen_hubert a training area to learn and teach thievery skills