Posted on 2 Comments

Advantage and Disadvantage in D&D Next

Advantage and Disadvantage in D&D Next: The Math
Originally Posted on May 24, 2012 at OnlineDungeonMaster.com


rotd-diceEveryone will be sharing opinions about D&D Next today and for the foreseeable future. I wanted to do something a little different and focus on just one thing: the math behind the Advantage and Disadvantage mechanic.

For those who haven’t read the playtest material yet, if you have Advantage for a die roll, you get to roll twice and take the better result (kind of like the Avenger in 4th Edition). If you have Disadvantage, you have to roll twice and take the worse result.

In reading through the rules, I noticed that being blinded gives you disadvantage for your attacks, while being prone gives you the same -2 to your attack that you would get in 4th Edition. So what’s the impact of disadvantage? Is it similar to a -2?

 

Averages
My first thought was, what’s the average of 2d20 keeping the highest (advantage), and what’s the average of 2d20 keeping the lowest (disadvantage)? I know that the average of a single d20 roll is 10.5, so knowing the average of advantage or disadvantage should tell me whether it’s equivalent to +/-2, +/-3 or what, right?

I decided to simulate this by having Excel roll a whole bunch of dice (over a million pairs of d20 rolls) and then taking some averages. For those fellow Excel geeks out there, my d20 roll formula is: =ROUNDUP(20*RAND(), 0). I generated two columns of these, then a column that was the maximum of the two results (=MAX(A2, B2)) for advantage and one that was the minimum (=MIN(A2, B2)) for disadvantage.

I got a result of about 13.83 for a roll with advantage and 7.18 with disadvantage. I later learned that the precise values are 13.825 and 7.175.  Comparing this to the 10.5 average you get for a single d20, advantage adds 3.325 to the average roll and disadvantage subtracts 3.325.

Done! Right?

 

It’s not all about the averages
However, as my fellow EN Worlders soon pointed out, this isn’t the most useful way to look at things. In D&D, what you care about is your chance of success or failure on a die roll. And when you change the distribution of results from a uniform d20 roll (equal 5% probability of every number from 1 to 20) to the maximum or minimum of 2d20, the impact is not the same as a straight plus or minus to a d20 roll.

The most useful way I’ve found to look at this is with the following table. The first column shows you the target number you need to roll on the die in order to succeed. (Note that if you need an 18 to hit but you have +6 to hit, then the target number on the die is a 12.) The second column shows the percentage of time you’ll get that result or better on a single d20 roll. The third column shows how often you’ll get your number with advantage, and the fourth shows the same for disadvantage.

 

What does it all mean?
Let’s take an example from the table. Assume you need to roll an 11 to succeed. With a straight d20, you have a 50% chance of success. With advantage, this goes up to 75%. That’s the equivalent of a +5 bonus to the roll, since you would also have a 75% chance of success if you only needed a 6 or better on a single d20. Pretty impressive!

On the flip side for the target of 11, disadvantage means you only have a 25% chance of success, equivalent to a -5 penalty to the roll (when you need a 16 or better on a d20, you also have a 25% chance of success).

So does that mean advantage/disadvantage is equivalent to +/- 5? Not all the time. In fact, it’s only that big when you need exactly an 11 on the die.

Let’s say you need a 15 on the die to succeed. With a single d20, you’ll only get this 30% of the time. With advantage, you’ll get it 51% of the time – about the same as you would get an 11 or better on a single d20. So advantage in this case is worth about a +4. Disadvantage, similarly, is about a -4: You only succeed 9% of the time with disadvantage, which is about the same as a single d20 with a target of 19.

At the extremes, advantage makes the least difference. If you need a natural 20 to hit, that’s only going to happen 5% of the time normally. Advantage ups your chance to 9.75% – equivalent to getting a +1. Disadvantage takes your chance down to 0.25%, or 1 in 400. That’s the chance of rolling back to back criticals – not a common occurrence. But in terms of a modifier, it’s not much different from giving you a -1 to your roll when you need a 20 – it’s just about impossible.

 

7-dice-setIn reality
Most of the time, D&D tends to set things up so that you need somewhere between a 7 and a 14 to succeed on a task unless it’s trivially easy or ridiculously hard. If you look at the percent success in the d20 column for those rows, then find the equivalent percent success in the Advantage column, you’ll see that this is usually similar to getting a +4 to +5 bonus to the roll. Disadvantage is exactly the same in the opposite direction.

So there you have it. For target die rolls that are reasonably close to the middle of the range, advantage or disadvantage is about the same as having a plus or minus 4 or 5 to your die roll. It’s pretty powerful – much more powerful than the +2 for combat advantage that you get in 4th Edition.

Note that I haven’t factored in the additional chance of a critical hit with advantage, since I don’t really care about damage per round or anything like that. Suffice it to say that your chance of critting with advantage is 9.75% instead of 5%, and you can do the rest from there.

 

 – Michael the OnlineDM

Michael Iachini, known in RPG circles as the Online DM, has written extensively about playing RPGs online at onlinedungeonmaster.com. These days you can mainly find Michael designing and publishing board games at claycrucible.com. Follow Michael on Twitter @ClayCrucible. 

 

 

Do you have a contribution or idea for Meta Thursdays?  Send us your ideas (after reading the submission guidelines) to submit(at)adventureaweek.com with “Meta Thursday” in the subject line!

Posted on Leave a comment

Tactical Intelligence

When I was younger I thought my dog Coppernicus (“Copper”) was about as dumb a canine as could be.
He was way too excited to be inside regularly and would get tangled in the posts of the back porch all the time (note: we made him a carpeted, insulated, heated dog house).
Turns out I was wrong.
Apparently my dad once took some lunchmeat and left it out of Copper’s tangled reach, then went inside. Copper barked for a while, then my dad shut off the kitchen light and moved back to the hallway. My dog barked a few more times then looked around to make sure nobody was watching before untangling himself to retrieve said treat.
Mike Myler
I was stunned. Copper was [he passed away some time ago; I am positive he’s humping his heart out in doggy heaven -MM] a stupid dog that humped everything and ate linoleum; that clever little pooch tricked me!

What on earth does this have to do with tabletop gaming?
My dog was using tactics.
All by himself. With no impetus other than to get attention, so not even with the kind of fervor or drive you’d expect from say, a wounded dire bear or starving wolverine.
More importantly, he showed a genuine understanding of his surroundings; Copper didn’t just trick me, he did it using terrain.

Don’t forget about using the land around creatures; whether you declare that the wolf knows it is on higher ground or not, take advantage of terrain features when using combat because as I’ve learned, even less intelligent animals can do so effectively. 
For sake of ease, here are some examples of how a creature with relatively little intelligence (1 or 2) might reasonably make use of their surroundings in combat:

  • WolfA pack of wolves has learned that some high-hanging brush proves bothersome to taller creature, and attempt to draw their opponents into it.
    • Treat the brush as difficult terrain for other Medium sized creatures that grants 50% concealment to all wolves and characters of Small size
  • Lumbering through the woods, a particularly gluttonous dire bear has found several meals after accidentally knocking down larger trees onto unsuspecting (and otherwise unnoticed) prey.
    • Starting from 60 feet away, give PCs Spot/Perception checks to notice the bear before asking for Reflex saves (DC 15 for half damage; 4d6 bludgeoning) as it knocks a tree down onto them to begin combat.
  • A feral deinonychus lairs within a deep cave; more than one unsuspecting explorer has wandered into its home and after several such encounters, the reptile has learned that taking away a light source ensures its victory.
    • After briefly assaulting an opponent and then fleeing within the cave, the dinosaur will perform the same to anyone that follows it, attacking whomever carries the light before running once more into the darkness, hoping to corner someone who does not benefit from low-light vision.
  • In the mountainous regions a wolverine has unknowingly mastered an extremely brutal version of the game King of the Hill with other, lesser predators.
    • Attacking the PCs in a rocky gorge, this wolverine makes use of a sloped pathway covered by boulders. The creature always moves to keep the higher ground, gaining a +1 to AC and attack rolls with the advantage in height.
  • Image_Portfolio_101_Fantasy Jason Walton 01After being attacked by countless adventurers using ranged weapons, a fierce dire tiger has realized that its jaws can easily snap a bowstring or pry the weapon away. More experienced combatants came to the fore and have fallen to the jungle predator as well, though now it can recognize the scent of spell components and knows exactly how dangerous they are.
    •      Rather than make an attack on a creature using a ranged weapon, the great cat attempts to sunder bowstrings or disarm archers before closing in for the kill. Should anyone cast a spell using material components, however, they will quickly find themselves targeted by the dire tiger until they’ve divested themselves of said items.

Remember: it’s your game and it’s up to you to decide just how intelligently creatures fight. As I described above, even the most innocuous, dumbest (albeit happiest-looking) canine can be surprisingly canny. 
Don’t be afraid to really challenge your players by taking advantage of flanking, creatively using terrain and performing more complex combat maneuvering than, “the beast charges forward and attacks you!”

Do you have a contribution or idea for Meta Thursdays?  Send us your ideas (after reading the submission guidelines) to submit(at)adventureaweek.com with “Meta Thursday” in the subject line!

Posted on 2 Comments

5 Tips when Introducing New Players

thiefWhen a new player sits at your table, or when you’re bringing an entire group their first roleplay experience, take a second to be objective about how you’re going to go about it. I’ve succumbed to the same impulse I see plenty of other GMs fall prey to—you want to bring the whole gravitas of what’s going on to your friends.

This is a great motive, but think about that; how intensive can you expect their first game to be? Are they prepared to read a great deal of rules before the first session? Will they want to? What about comprehension; will players really grasp the rules without a visual example demonstrated in front of them?

So put away the 5th level pre-generated PCs you’ve made for the epic journey soon to be taken by the newbies—save them for later, after you’ve doled out a taste of what’s waiting for them down the road.

1. Character Creationdwarf2
This is a topic we’ve visited before, but I’d like to address another issue. If you’re playing Dungeons and Dragons 3.5 or another system with generally slow character advancement (in terms of varied mechanical abilities; more feats, spells, powers, etc.) then 2nd level is not unreasonable. If you’re doing Pathfinder or a game where characters accrue new abilities (read: rules) every level, consider capping things at 1st. You can level them up after the first game if it seems that things went alright, but honestly, if you can remember your first game, the opening of a truly dynamic game world is probably enough to keep them busy anyway.

2. Permanence
Create a real sense of place. Make a map of the town the game starts in and quiz your players on what it is they do on a regular day after you’ve described the setting. Even a high-action game has to start somewhere, and creating a realistic environment for people new to the experience is key in starting immersion—when they start investing time with reading through the rules, the hook is in and you’re free to reel in the line.

priestess3. ROLEplay
Allow folks some time (maybe an hour in-game, maybe a day) to familiarize their characters with one another—banter, establish nicknames and what have you. At the end of the session, you want your players to walk away with a solid connection to their characters. Letting them shape their characters into people all their own is an essential part of that process.

4. Combat—Intriguing but Inuitive
Let them win the first one and don’t overshadow them. I personally like start with a combat against a single one-level higher physically-based NPC, talking up his part substantially beforehand and putting an emphasis into one trait (Strength, Dexterity or Constitution). Statistically, they are bound to go down eventually but not before making the PCs feel like swaggering afterward; it’s going to take a fair number of rolls to beat the average-unlikely statistics behind that NPCs build, so (while inevitable) success appears to be in question.

middle-ages-clothing-25. FUN!
I hate it when people use this word as a title, but honestly, this is the point of gaming. You are supposed to be having fun; even if there’s supposed to be a TPK, don’t let the entire group perish in their first game and intercede if necessary. Provide them with a guide if they’re really at a loss for how to proceed with the game itself and then ditch that NPC as soon as they start to ride the roleplaying bike.

 

Do you have a contribution or idea for Meta Thursdays?  Send us your ideas (after reading the submission guidelines) to submit(at)adventureaweek.com with “Meta Thursday” in the subject line!

Posted on Leave a comment

A Design Exercise in 4 Steps from Concept to Mechanics

hobgoblin_leader__storn_cookThe character in your head (PC or NPC) fits the vast majority of thematic requirements for the game or campaign you’re about to join, but none of the abilities available fit what you want. Homebrew is hardly unheard of, but nobody wants to waste time arguing over some house rules—you need a strong set of mechanics that the GM and other players can fully approve of.

#1) Idea
Where do we start? How do we take an idea from our brain and onto the table in an intelligent, responsible fashion? First, obviously, we need an idea.
For today’s purposes, we’re going to be using “Speedball” from Marvel Comics as our example (I was a big fan of his up until the whole Penance business—I’ve even got most of the first run of the terrible solo issues). making up a very basic framework for an equivalent in Pathfinder. For those not in the know, Speedball could basically make himself into a big bouncy ball, redirecting kinetic energy.

#2) Search
The first thing to do is see if the tools are there already or not. While the PRD is fantasticwhen it comes to designing something for Pathfinder, you should be using d20pfsrd.com. John Reyst and his slew of minions are constantly adding 3rd Party Publisher material (so you know your design is unique), have a more accessible search engine (use those quotation marks, folks) and you can break up results by category (this saves an enormous amount of work vis-a-vis magic items, classes and spells).

133-Chained-library-at-Wimborne-Minster-1709x1021Let’s look up some keywords for Speedball’s abilities: “bounce”, “bouncing”, “kinetic” and “redirect”. Whenever possible, we want to mirror or incorporate the established mechanics set up within the RPG in question, so don’t be lazy about looking at what comes up. Most of the page counts shrink as well for some reason, so sally forth!

Bouncing Spell—We’re not really doing anything with this. If I was writing an entire base class, this would absolutely become a part of it somehow, but we’ll stick to levels 1-5 if we go that route, and feats or a simple archetype if not.
Greater Ring of Bounce—A cursed item that gives a +10 bonus to Acrobatics check for jumping, but a -10 for any other use, CL 7th. This sounds like something we can use, so we’ll put a star by it to remember, and maybe a note. [***attack ability?]
Bounding Hammer—From Pathfinder Companion: Dwarves; on a successful hit with a thrown hammer, the feat makes it land in your square. [*** feat to catch thrown weapon]
Roll With It—This goblin feat looks like we’ve struck gold. Take a melee hit, make an Acrobatics check (DC 5 + damage) as an immediate action, success means that you take no damage but move in a straight line (in a direction of your choosing) 1 foot for each point of damage you would have taken, halting after half your speed in movement. Run into something and you take 1d4 damage and go prone, and all that movement provokes AoOs. Worse yet, you are staggered for a round after attempting the feat. [***fundamental]
Tumbling Descent—This roof runner rogue archetype ability from Ultimate Combat fills another great gap: so long as there are two surfaces no farther than 10 feet apart to bounce against, they can fall indefinitely with an Acrobatics check (DC 10 + 5 for every 10 ft. increment descended beyond the initial 10 ft. drop) [***fundamental]
Shield of King RytanRicochet Shield—This is an interesting combat trick; a -2 attack roll penalty to bounce a thrown shield around an 
obstacle, with a note about range increments for total distance traveled rather than from wielder to target. [***attack ability?]
Bouncy—Another goblin feat from the Pathfinder Player Companions; the first 1d6 lethal points of falling damage are automatically converted to nonlethal damage, and you get a +2 Reflex save to avoid unexpected falls. [***the cushion effect]
Kinetic Reverberation—This 2nd-level wizard spell lasts rounds per level, allows for SR and a Fortitude save. On a failed save, the weapon striking the target enchanted by this spell takes the same amount of damage it dealt to the target. Doesn’t effect natural attacks. [***fundamental]
Impact—For the equivalent of a +2 weapon enhancement bonus, increase a weapon’s damage die; CL 9th. Good stuff to know. [***fundamental]
Redirect Attack—This advanced rogue talent allows a once per day redirect of a melee hit to strike an adjacent creature as a free action, requiring the attacker to roll a second time. Definitely high part of our core concept. [***fundamental]
Flowing Monk—This guy has quite a bit of what we’re looking for: redirection, unbalancing counter, flowing dodge and elusive target (as well as the Elusive Redirection feat) fit the bill for our core concept. [***fundamental]

At least he's not weaing skin-tight red leather...

#3) Assess
Our design ends right here. We could break some of this down and rebuild the pieces, creating a more specific monk archetype (the bouncing goblin, perhaps?) but as it is, a goblin flowing monk with the right feats, a few errant class levels or new magic items and a bright attitude should do it.
A lot of our work is done for this guy—let’s assume we make a goblin flowing monk 5/rogue (roof runner) 2. They can flow around attacks via flowing monk abilities (and, of course, the Crane Stance feats), with the Roll With It feat they can redirect movement from a solid hit, they can bound downwards with tumbling descent and slow fall, and on top of all that, jump extremely far thanks to high jump. None of the flowing monk’s abilities prohibit shields, so next level we grab up fighter and a feat for tossing things, keeping a few hammers around for the purpose; if we can manage it, with the impact quality. For good effect, I’d throw in the Mobility feat somewhere to avoid those AoOs.

I’m not at all bummed, by the way. We didn’t even it make it to the repeat of step 2: searching for 3PP material to see what else can be (or has already been) done (hint: Trick Shot from Psionics, along with other Marksman things). That’s one of the reasons Pathfinder is so excellent—there’s rampant versatility even within the core rules. We’ll take another shot at something totally original next time..

#4) Design
What didn’t we pick up along the way here? We’re going to miss out on Redirect Attack, but that’s hardly the end of the world. Kinetic reverberation is something we can work with however.
Let’s head back to d20pfsrd.com, do a search and click on magic items—nothing shows up, so we’re clear for liftoff.
Of course, firsthand knowledge never hurts (ideally I’d be hip-deep in Paizo books for “research”) and I have an example from a Magic Item Monday back in September. While I obviously liked it, we want our goblin flowing monk/rogue to use some kind of impact weapon anyway. We could get the quarterstaff enchanted, but then the shield aspect is gone.
Instead of enchanting the weapon, what about making an enchantment that activates a kinetic reverberation?
gauntlet-12We want something like a cape of the mountebank—activated on command with limited uses per day. This is a math problem now [(CL 3rd) x (spell level 2nd) x 1,800 gp] divided by (5 divided by 3 charges per day) = 6,480 gold. It’ll be costly to buy at 12,960 gold pieces (assuming we don’t have a buddy with Craft Wondrous Item), but our goblin flowing monk will now have bracers of rebounding strike that can be activated 3 times a day, granting 3 rounds of weapon damaging, kinetic action
 (Fort DC 13) with each use.

Maybe next time we’ll get lucky and hit the fields, but today we’re staying in the stables. Now, however, I am genuinely interested in putting together an elusive little goblin monk and am surprised I haven’t already…perhaps that will be something to be see in the upcoming Sidequest Saturdays? 😉

Do you have a contribution or idea for Meta Thursdays?  Send us your ideas (after reading the submission guidelines) to submit(at)adventureaweek.com with “Meta Thursday” in the subject line!

Posted on Leave a comment

4 Tips to Stop the Monotony in Random Encounters and Surprise Players

Image_Portfolio_101_Fantasy Jason Walton 12Everybody can enjoy the nocturnal prowling of beasts, but eventually troll raids can get a little bit stale. When the party goes off-course and the third evening of animal attacks comes to pass, consider a few alternatives to keep your players on their toes. Any NPC could be led to act as a random encounter for the party, hired or tricked by rivals or nemeses, following a falsified bounty or another case of mistaken identity or even simply be opportunistic bandits.

Here are a few of the things I keep around when I’m GMing to make sure my group remains alert and engaged when they’ve fallen foul of a random encounter:

  • Keep a collection of pre-generated NPCs near the party’s level (if you’re trying to save space or ink, keep it to NPCs of a higher level than the party.)
    • Don’t have the time to stat them all out? Do you have old character sheets? These are good to have around for surprise guests at the table or if a player dies unexpectedly at the beginning of a session and doesn’t want to miss out on all the action, but can definitely stand in as mercenaries, bounty hunters or misguided enemies.
      • For some extra fun, get your players to lend you their old sheets; just make sure to reward additional XP, not to give out too many magic items, and of course to change the NPC’s name.Image_Portfolio_1.14_Fantasy Butch Mapa 12
  • What about the plethora of NPCs here at AdventureAWeek.com? There are dozens of adventures for parties of every level. Bookmark your favorite characters (they all have hyperlinks for both D&D 3.5 and Pathfinder) when you browse through the modules for referencing later!
  • For the Pathfinder players out there, there are three extra suggestions I have for you:
    •  The first is the simplest: get familiar with the NPC Codex. There are characters for every core and NPC class, levels 1-20; I bought a copy and am super happy that I did.
    • The second is a little bit more complex but ultimately worth it: grab File Off the Serial Numbers. Within it, Sean K. Reynolds explains how to quickly strip down a monster and have it act in a different role (turning monsters into monks, clerics, wizards and paladins).
    • Don’t forget about haunts and cursed items! The AaWBlog has been consuming them for some time, and there’s already several in its gullet!
  • Sometimes monsters are unlikely or in unexpected places. If your campaign setting is a place of moderate to high magic, what’s to say an awakened animal (which could quite easily gain fighter levels) or creature far removed from its normal stomping grounds hasn’t taken the territory by chance?

Image_Portfolio_1.13_Fantasy Rudolf Montemayor 08

Whether the party is in a dungeon, on a mountainside, sailing the seas or resting in a wooded grove, if they’re there, there’s always the possibility that similar adventurers or explorers might be as well. Don’t be afraid to challenge your group with some of the suggestions above if things seem to get dull.

 

Do you have a contribution or idea for Meta Thursdays?  Send us your ideas (after reading the submission guidelines) to submit(at)adventureaweek.com with “Meta Thursday” in the subject line!

Posted on Leave a comment

Two Thorns in the Grand Lion’s Paw

AAW-SonicCicada-colors01Creature design can be a tough road to walk and even the most seasoned, stalwart player can lose their nerve when their nefarious monster brings them low.

This isn’t a sign that either one of you is necessarily doing anything wrong; as far as I’m concerned, it means that you’re about to crest the wave of serious immersion. Drama is high and there is a real, palpable danger to the PCs and if they aren’t preparing their things to go home, you’ve done it and you’re riding the wave.

How do you stay on the board? Weaknesses: one generalized and (to get unique) one rare.

 

My favorite example of this is from the Paizo core rules – take a look at the Jabberwock—specifically, DR 15/Vorpal and cold vulnerability.
That’s pretty specific and you know what? That’s great. A dedicated party of high-level adventurers would still be able to drop this creature, whether properly equipped for the task or not. The latter will prove to be a real challenge, but the former won’t be a pushover.

 

If you’re making any monsters yourself (and you should be – always throw a curve ball at your players) take a note from the Jabberwock.pyro

This creature brings into focus one of the principal elements in monster design. It’s clearly in the realm of high-level encounters, and it shows without having to read the slew of offensive abilities at its disposal. Following the progression of the Pathfinder Monster Creation Rules, its hit points, AC and saves fit the bill and are on average what they ought to be, so why the weaknesses?

 

The answer is a simple one: high-level encounters mean high-level abilities and powers.

A formidable, high-level combat-proficient PC (barbarians, fighters, paladins, rangers and rogues) will unleash a considerable amount of damage each round from weapons, chipping away at that stack of hit points with a fair amount of success (at that point, the frequency of critical hits rises quite a bit). Without a truly effective form of damage reduction—take a seat, adamantine—the Jabberwock will fall far sooner than any GM is going to be happy about. If a potent spellcaster is around, this wonderful “dragon” would be biting the dust if it wasn’t loaded with resistances.

 

The specificity of the vorpal enchantment means that the PCs are unlikely to have more than one or perhaps two weapons capable of completely ignoring it’s physical buffer, and the resistances (at double the value of the DR) do the same for magical attacks—any lower level spells, like fireball, are going to be practically ignored unless they produce a cold effect.

 

Gremlin final cropMonsters like the Jabberwock are unique examples of truly creative design work. This one creature can easily occupy a huge number of opponents, withstand the attacks of fell foes, while still possessing an attainable Achilles’ heel to reward the smart, prepared adventurer.

 

If you’re making a mid- or high-level monster, make sure to learn the lesson of the Jabberwock – prepare for the worst (buffer) and hope for the best (selective and generalized weakness).

[Hey, did you know I have a twitter account? The myths are true. -MM]

Do you have a contribution or idea for Meta Thursdays?  Send us your ideas (after reading the submission guidelines) to submit(at)adventureaweek.com with “Meta Thursday” in the subject line!