Calibrating Compasses

I've been opposed to having compasses in my D&D games for a good long while, on a couple of grounds.  They don't really fit into a Dark Ages or Ancients milieu, and it seems intuitively obvious to a suburbanite that they should sort of trivialize navigation.  The latter, I am learning, is not quite true.

I have been doing some pre-reading in the Annapolis Book of Seamanship for a coastal navigation course I'm taking this winter, and was surprised to learn that when installing a compass on a vessel, you need to calibrate it.  Ferrous metal fixtures on the vessel can interfere with the compass' accuracy, and that interference changes as the vessel changes heading.  There are some fine adjustments you can make to modern compasses, but those probably weren't available on compasses in the Bad Old Days, and even today these fine adjustments can sometimes be insufficient, in which case you end up writing up a table of adjustments to the heading the compass shows based on the heading of the vessel - a mapping from apparent magnetic heading to actual magnetic heading.  And making that table requires having precise bearings from where you're carrying out the calibration.  Apparently "compass adjuster" is something of a specialist profession.

And then magnetic north is off from true north, and the amount you have to compensate for that varies based on your location - if you're between the magnetic north pole and the actual north pole, the difference could be 180 degrees!

I was talking about compass deviation due to metal fixtures at work and an ex-army colleague mentioned that when he taught overland navigation, one of his pastimes was giving the compass to the squad's radioman and seeing how long it took the squad leader to figure out that the radio was interfering with the compass.  "Machine gunners were OK too, it's a big piece of metal."

There is also a note in the book that "Very few steerers [helmsmen] are good enough to keep a boat within 2 degrees of course in smooth water; in rough weather, steering errors of 5 to 10 degrees are common."  One side of a hex is 60 degrees wide, so a 10 degree error in rough weather is one hex side every six hexes or so...

All of this is to say that if you allow compasses in your games, they aren't necessarily an end-all-be-all for navigation.  Full plate may mess with your compass, magic items might mess with your compass ("magnet" and "magic" share a prefix, after all), magnetic "north" in your setting may be in an interesting spot or just move around a lot, and even if you have bearings there's still room for error in steering to lead to course deviation.  To say nothing of the quality of nautical charts and other maps in pre-modern times!

Vermintide 2's Special Enemies and Encounter Design

Status: D&D related, possibly obvious

Vermintide 2 was free on steam the other weekend and my brother and I have been playing it together.  We've been trying to play it with the mechanics unspoiled to keep a bit of sense of wonder/surprise in it.

Something that stuck out immediately was the special enemies.  This is really a common design pattern in team horde FPSes - Left For Dead and Deep Rock Galactic both have analogs (and I like DRG's term for them - "disruptive" enemies).  These enemies either deny you terrain and visibility (with, for example, a big cloud of poison gas) or suppress/disrupt an individual player (for example by grabbing a character, preventing them from attacking, and dragging them away from the party) until either the target or the special enemy is killed.  They aren't especially tough and their damage output isn't enormous but they require pretty immediate action or they can seriously degrade the party's ability to fight the horde of fodder enemies who usually accompany them.

Vermintide got me thinking about this from the D&D angle for two reasons - first that unlike DRG it is low-ish fantasy, and second because it makes these special enemies very high-visibility.  The player characters call them out in game (at least on the difficulty we're playing), many have literally high-visibility glowy bits, and killing them is mentioned in the post-mission statistics screen, which makes it clear that they're thought of as a class or category of enemies.

(The other two called-out classes, Elites and Monsters, also bear consideration.  Elites we think are tougher versions of normal enemies; they may be better armored or hit harder and bear special consideration on those accounts but they're not especially disruptive to party cohesion / positioning.  Monsters are creatures much larger than a man like trolls or rat-ogres that, as least as far as we can tell, require pretty much the whole party to fight them concurrently, with lots of HP and a boss healthbar, and often a combination of multiple damaging attacks, throws, grabs, area denial, and other abilities that you might expect of a Special but on a much beefier frame)

Meanwhile, in OSR D&D, we have critters that have disruptive abilities like a Special but we're mostly not using them in combination with regular enemies.  Consider mummies.  Mummy paralysis is a big disruptive ability and anybody left with freedom of action has the onus on them to kill the mummy immediately (or at least bait an attack out of it) to end the paralysis.  But mummies are their own monster type with their own lairs and if you're stocking by the book you're never going to get an encounter with 15 zombies or skeletons and one or two mummies - the fodder+special combo.  Or, if mummies are too high-HD and durable and fall closer to the Monsters category, 15 zombies and two ghouls.  A gelatinous cube plus a bunch of skeletons would be an encounter to remember, but it won't ever come up in prep (though it could potentially happen in play through a combination of a fixed skeleton encounter and a lurking threat cube making its move as the party is dealing with the skellies).  The best we've got are witchdoctors and shamans with beastman lairs - and those are wilderness lairs, not dungeon encounters, and if you're rolling random spells for your witchdoctors they're usually either duds or TPK threats instead.  In beastmen too we have something like Elites in champions and chieftains.

But the fodder+special combo seems like the sort of thing you'd want to use if you were building dungeons to challenge your players.  And this whole line of thought also ties back to breaking up the phalanx - enemies who deny choke-points, grab front-liners, or bull-rush through them, all seem like good tools for diminishing the power of the shield-wall in the dungeon, but I haven't been thinking of them as a category.

Is this too 3e a thought?  Is this something 4e did explicitly?  Does this place too much emphasis on tactics of individual combats in OSR games where combat options are relatively scarce so parties may not really have any means to respond to disruptive enemies - games where the emphasis is generally on the expedition as a whole anyway?  Is this even worth considering in prep or is it good enough if it can happen randomly in play?  I really don't know.  But it might bear experiments, and seems like a useful schema / category with which to think about monsters in tabletop games.

Beastman chieftain abilities might be a really easy place to start with procedurally-generated fodder+special combos.  One could design abilities with the special/elite distinction in mind, and then push them down to subchieftains so that they start showing up in dungeon lairs.

Maybe another angle to consider is strategically-disruptive enemies: expedition-disruptors rather than single-combat-disruptors.  If the focus of the game is on the expedition and we're worried about there being too few in-combat options, maybe it makes sense to shift one level higher.  The Crypt Thing might be a really good example of this - its teleport doesn't just take a character out of a particular combat temporarily, but disrupts the expedition as a whole by scattering the party throughout the dungeon.

But what does combining expedition-disrupting enemies with fodder look like?  Maybe just random encounters being triggered by a disrupted party taking more time to recover.  Maybe nothing at all needs to be done and OSR D&D is just fine the way it is.

AD&D's Artifacts (or Relics?)

I'd been meaning to take a closer look at the 1e DMG's section on artifacts after noticing during my previous skim that there were a bunch of blank lines that looked like they were meant to be filled in by the DM.  I finally got around to it today and what I found was even wilder than I expected.

Surprise #1: you can roll artifacts on the random treasure tables.  A 17 on the d100 on table III.E.1, Minor Miscellaneous Magic Items, is "Artifact or Relic (see Special table hereafter)".  And then you roll a d% on table III.E.Special and an 01 is the Axe of the Dwarvish Lords and a 100 is the Wand of Orcus and everything in between is on that same level.  Since rolling on the main magic item table has a 3% chance of going to table III.E.1, any magic item roll has an 0.03% chance of yielding an artifact - about 3 in 10,000.

That doesn't seem like a crazy-high probability, and it's pretty awesome that you can roll them randomly at all.

There is a note that if you the DM don't want an artifact in your campaign you can instead replace it with a Bag of Beans, an actual minor magic item.  Which I'm sure many DMs did, but I imagine that letting the dice even suggest an artifact at random would probably increase how often we see them in play.  I also like this bit (emphasis mine):

Regardless of how any of these items come into your campaign, only 1 of each may exist. As each is placed by you or found by player characters, you must draw a line through its listing on the table to indicate it can no longer be discovered randomly— if the dice indicate an item no longer available, you may substitute a clue as to its whereabouts or simply ignore the result so that no magic item is found at all.

And in a big 1:1 timescale campaign game with patrons, "where it might be found" might well be with some other player's character.  The Teeth of Dahlver-Nar also seem much less insane when considered in a large-campaign context.  This is a set of 32 artifact-tier teeth and the more of them you collect the stronger the effects get.  Hunting down 32 teeth individually as a single cohesive party would be a huge slog, but if you have multiple adventuring parties operating in parallel across timespans of years, accumulating a significant number of these seems much more plausible.  This is probably true of the other "set" artifacts like the Regalia of Might and the Rod of Seven Parts as well.

Anyway, what's up with these blank lines with roman numerals in each item's description?

Because of the unique nature of each artifact and relic, their powers are only partially described. You, the Dungeon Master, must at least decide what the major powers of each item are to be. This prevents players from gaining any knowledge of these items, even if they happen to own or read a copy of this volume, and it also makes each artifact and relic distinct from campaign to campaign.

(Again, emphasis mine)  This too is awesome.  And then there are long lists of candidate entries for each roman-numeral type.  I and II are minor and major benevolent powers, III and IV are minor and major malign powers, V are prime powers, and VI are Side Effects.  The balance here seems a little uneven; some of the minor benevolent powers seems competitive with some of the major benevolent powers, and the Side Effects are a very mixed bag, with some rather brutal curses and some pretty neutral or maybe even useful effects if clever.  The prime powers are ridiculous.

Other possibilities include the ability to cast resurrection 7 times per week, meteor storm once per day, finger of death with no save once per day, wish once per day.  We're not in Kansas anymore.

The counterbalance to these are the Major Malign Powers, which trigger when a prime or major benign power are used.  These are also excellent.  "User is instantly killed but may be raised or resurrected", for example.  Many of these feel unreasonably punitive for some of the major benign powers (ex Speak With Monster 2/day), but for keeping Prime Powers in check, yeah, these seem appropriate.

Another interesting thing here is that these lists aren't rollable tables; they're labeled with letters (and then doubling up, X, Y, Z, AA, BB, CC, ...).  This has to be intentional.  Gygax doesn't want you rolling randomly a "wish 1/day" item.  Gygax also doesn't want you to roll an Axe of the Dwarvish Lords that kills you every time you use it to cast Speak with Monsters.  Gygax wants you to stop and think about these superweapons you're considering handing out.  Apparently this is where the line gets drawn for random generation.

The section on destroying artifacts is also pretty good.  Some of them involve killing gods or demon lords.  And since gods and demon lords have stats in the 1e Monster Manual and are on the random encounter tables, this could actually happen in play.

The term "artifacts and relics" is also interesting.  Relics in real life are "the physical remains of a saint or the personal effects of the saint".  "Relic" is a much tighter noun than "artifact", and captures the nature of a lot of the artifacts well (for certain values of "saint").  It's kind of a bummer that "artifact" caught on as the term here.

I think the relationship with sentient swords here is also significant.  These are sentient swords turned up well past 11.  Sentient swords zap you for damage if you're the wrong alignment; some of these relics will save-or-die you if you're the wrong alignment (or just low-level).  Some of them have ego and intelligence scores and will have personality conflicts with you just like sentient swords.  But they seem like they might have the same job as sentient swords, of giving non-spellcasters access to limited spellcasting capabilities, of helping balance high-level fighters with high-level MUs, but at the very high end.  The big difference is that sentient swords are lower power and balanced primarily by Ego to keep high-power swords out of the hands of low-level characters, while artifacts are all high-power so that Ego balancing mechanism falls by the wayside and is instead replaced with permanent costs/risks to the characters using them.  Which is also why you can get away with single characters using multiple artifacts when they could only use one sentient sword at a time - multiple artifacts give you more options, but you still have to pay the Major Malignant price each time you use one.

I'm now rather curious to go see if OD&D had artifacts.  I don't recall them from the LBBs or Greyhawk.  It sounds like they were in Eldritch Wizardry but their effects may have been underspecified.  I'll have to give it a look I suppose.

In conclusion: lots of good stuff to steal here.