Schrödinger's Gun GMing: Monsters on the Fly

Welcome to another article in the Schrödinger's Gun GMing series!

So far we've talked about letting go of your GMing preconceptions about where an adventure begins, about Plot Points and making a Plot Stack for your game, and about Carrots and Sticks to motivate your PCs. Now that the party is engaged with the plot, what challenges do you throw at them?

For D&D and the vast majority of RPGs in general, the most common challenge standing between the party and its goals involves monsters. From lurkers who harry the party as they try to do something else, to stand-up soldiers doing their job for the Hobgoblin Army, to guards working for a megacorp, to the brutal giant alien that taxes the party to its limit, to the minions that protect the evil mastermind, to the dragon attacking the village, monsters come in all forms. You've got boss monsters for your major plot points ready to go, but how do you create something relevant to the situation and work out the numbers on the fly?

You could plow through a rulebook and refer to the monster's stats, but that wastes time as you flip through to find what you're looking for. Can you really fit another book propped open behind your GM screen? If not, you'll need to spend the time and copy the relevant stats to note paper. Also I've found that what's in the book rarely lines up exactly with what I have in mind. My solution? Break out your index cards and improvise!

How to Create and Use a Monster Stack.
The ever-handy 3x5 index card works for my style of GMing so that's what I use. I'll assume we're using index cards, but please use whatever format or technology works for your style of GMing.

1) Choose Base Monsters (Game Prep)
You know your world. You know the beasts and races that make up your world. Sure, there may be infinite variation to your world's flora and fauna, but it's unlikely you'll trip across a colony of Shambling Mounds in the middle of the desert, nor a clutch of demons spontaneously appearing in the middle of a busy street. These are plot-level decisions. If they happen, there needs to be a good in-game reason for it or the players won't buy into the reality of your game world.

Or, y'know, Drow with Sword, Drow with Bow, and
their erstwhile companion, Drow with Spiked Chain.

Take a moment and think about the monsters that your party is likely to fight over the next few sessions. Chances are you'll come up with only a handful of basic critter types. And when I say "critter types", you can take that as species (goblin, dragon, piercer, etc.), or you can take it to mean type (lurker, artillery, brute, etc.), or a blend of the two (Kobold Rogue, Drow Sniper, Fire Giant Warrior, etc.). Use whatever delineation makes sense to you, but stick with a handful of basic types. For instance, if you're going into a Drow settlement, chances are you'll meet nothing but Drow, so I'd go with Guards, Priests, Wizards, and Rogues.

Once you have your basic monsters, assemble game scores for them as needed. You can set this up however you want, but I've had good luck with 3x5 index cards in my D&D 3.5 game. As a bonus, the 3x5 cards stack well, so they serve double duty as my Initiative Stack in combat.

2) Make Templates (Game Prep)
Now that you have your base monsters, choose how they may be different and unique. I'll call each modification a Template, but it can be whatever change that makes sense - new skills or descriptors, different powers, a new weapon package, Enchanter instead of Evoker, whatever you need to throw curve balls at your party.

Art by UrsalaV.
Template by The Looney DM.

Most templates you already know how to make. For example, a Fire creature would use fire instead of any other energy type, be resistant to fire, and may have a damaging aura if they're actually on fire. A Berserker creature may have 20% more hit points, a couple points of damage resistance, an ability that lets them ignore special effects, and a huge axe that does an extra 1d8 of damage on a hit. Someone with a Sword of Shadow may be able to hit incorporeal targets and do +2d6 negative energy on a hit.

Note: Don't include percentages unless you're really quick at basic math. You'll save time simplifying to "+20 hit points" instead.

Whatever set of abilities and powers makes sense to you, note it down. If you use a 3x5 index card you can paperclip the template directly to the base monster. Just make sure your templates are easily accessible in whatever format works for you.

Pro Tip: Normalize!
I've normalized my share of databases in my time. One of the points of normalizing data is to avoid redundancy. When making monsters and templates, you want to make a few very flexible cards instead of a pile of single-use cards. If you have several monsters or several templates that do almost the same thing, then don't bother keeping them separately.

For example, if you're running an adventure in The Elemental Keep, you'll probably have several energy type templates. If each energy template adds 5 resistance, +1d6 energy damage, and an aura 1 that causes 1d6 energy damage, then I'd boil it down to one template called "Energy Creature". You can keep a list of energy types at the bottom of the index card. Now you have fewer cards with much more flexibility.

Unique boss monsters are a different story. You want your big monsters fully developed as solid story points in your game. I keep mine on index cards for later reuse just like base monsters, but I tend to improvise less with them. If you've already got an Infernal Black Dragon, adding a Cold template doesn't really seem to add anything except needless complexity.

1) Say "Yep, that would suck."
2) Show them this picture of Hugo.
3) Watch them cry.

3) Describe Monsters (Runtime)
When you need a monster at the table, forget about stats for a minute. Listen to what the players are expecting to see - sometimes they blurt it out and save you the trouble of guessing, like, "Boy, wouldn't it suck if that Ogre Barbarian was hiding right around this corner?" Take a look at the situation and ask yourself what would make sense.

Once you get a picture of what's hiding there for the PCs to fight, describe it as they experience it. This is most commonly a visual description, but don't feel limited to colors and sizes. "You feel something slimy brush your leg, then it's gone," works just as well. Use all the senses to describe texture, temperature, smell, noises, shaking ground, battle cries, sharp claws, crazy eyes, and flailing tentacles.

4) Assemble Your Critter (Runtime)
With your description in mind, pick a base monster and zero or more templates. If this is a quick encounter meant to slow the party down, a base creature is fine. If you introduce one of the guard captains, pick a template to make the encounter a little more challenging and unique.

When you choose a base monster, don't feel limited to what's described on the card. If y, feel free to use whatever stats come close and literally reskin the monster as a different race. If ou need human 4th level fighter guards and all you've got for prepped base monsters is an Ogre, use the Ogre's stats and swap in a long sword for the greatclub. If you need a juvenile Hill Giant, lower the damage a bit and use your Ogre stats. I've used a halfling Conjurer boss from previous adventures as a Drow Wizard guardsman who led with Acid Arrow and could summon spiders. The stats were close enough and it saved me the trouble of picking out spells in D&D 3.5.

Assembling a critter is as simple as choosing the index cards for the base critter and whatever templates you want to use. Use your best judgement and try not to overdo the templates, especially for quick or random encounters. Scribble the adjusted numbers down, and you're off to the races. With a little bit of prep work, you've just hacked a creature together to order in about a minute.

Just be sure to keep all
your knives in the air.

Pro Tip: Going Beyond Templates
If you really go off the rails, feel free to make up stats as you go. If you need to extend your fire template to make the critter immune to cold as well as fire, have at it. Adding a breath weapon and a vulnerability to wooden weapons? Go crazy as long as it makes sense in the situation. If you don't have a good template set up for what you want to do, wing it for now and prep a new template before your next session.

When winging it, look at the templates you've already made. Chances are you'll notice some patterns in the bonuses, like most templates grant a +1d6 damage bonus or base monster stats only change by 25% at the most. Use these guidelines to tweak your monster however you need to so it will fit the situation and the story.

Caveat Emptor
I wouldn't rely on this technique to create truly unique monsters. It's great as a start, but a one-of-a-kind boss monster will benefit from slightly more design work than hacking together a couple of templates.

When winging stats, remember that "different" and "harder" don't always mean "bigger" or "nastier". There's nothing terribly fun about fighting something that's impossible to kill, and if everything turns into a slaughter you're missing some great opportunities to throw social curve balls and moral dilemmas at the party.

I once made an orc wizard NPC who researched all things Dwarven in his quest for more power and greater knowledge. He tried to hire himself out to the PCs after escaping the slaughter of his clan. The party rebuffed him, thanks to the racial tendencies of the Dwarf among them. He ended up becoming a servant to a powerful Gnomish Alchemist, who changed him into a human so he could easily take part in human society. Instead of a one-encounter speed bump on the way to next level, his story got the players to question their motivations, however briefly, and he became a recurring not-quite-trusted NPC with a really cool backstory.

Wrapping Up
By investing some time in a tool kit for working with monsters on the fly, you make improvisational GMing much easier on yourself. The more base monsters and templates you make, the faster you'll be able to adapt something from your library to put into play immediately. Limit yourself to a handful of base monsters and templates during a particular session so you don't suffer from analysis paralysis, and feel free to swap monsters out if you get a minute of downtime, particularly if the party suddenly changes direction.

The main drawback to this method? It's a system-specific approach to monsters, and as such it's much better suited to campaign play rather that one-shot adventures. But there's no reason you couldn't run a sandboxy one-shot with nothing but a monster stack. You can keep a stack of Pathfinder monster cards next to your D&D 4e monster stack. It's just a little more prep work, and you get the advantage of cross-pollination when you adapt monsters between systems.

Have you used something similar in your games? How did it work for you? What did you use? Index cards? A spreadsheet? If you try this approach to running monsters on the fly, I'd love to hear how it worked for you in the comments below.

Thanks for reading!

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