I’m one of those gamers who is always looking for more customization. The more that I can fiddle with the mechanics and appearance of my character and my world, the happier I am. It’s one of the reasons that I was a fan of Need For Speed despite knowing nothing at all about cars. I didn’t know what any of the engine parts did—and fifteen years later, I still don’t—but I knew that swapping them out might make my car go faster. By that same token, roleplaying games that don’t allow for a lot of tinkering have a hard time holding my attention.

Customization is one of the great joys of being a dungeon master. Dungeons and Dragons, like most tabletop roleplaying games, is almost endlessly modular; you can take the ruleset and apply it to any setting. These settings can be full of dungeons, items, and creatures that you’ve created yourself. If you’re like me, the prospect of building your own world from scratch is incredibly exciting.

It can also be incredibly overwhelming. The infinite choices of your imagination can be a paralytic, pulling you in so many directions at once that you don’t know which is right. I’m here to reassure you that the only wrong answer is the one that isn’t fun for you or your players. Anything else is fair game.

Take, for instance, monster creation. There is an entire multiverse of creatures at your disposal for you to throw in front of your players, but you may have something specific in mind for your game, something no one else has quite approached in the way you’d like. In that case, you’ll have to come up with something yourself, or adapt an existing creature to fit your setting. But how to even begin? The Dungeon Master’s Guide has an excellent breakdown on how to build a creature mechanically, but the number of questions and moving parts may be bewildering for a newer dungeon master. Before sitting down to draft your monstrous new creation, here are five questions that I think will help give you direction and narrow your focus in the process.

What Purpose Do You Want this Fight to Serve?

Think about how you want your custom monster to challenge your players. Is this meant to be a drawn-out battle to the death, or a frightening ambush? Is this creature meant to be recurring, or are they disposable? A monster, as the designers of D&D have often said, is more than a sack of hit points. Ideally, combat is a vehicle for story and character development.

The more you think about the kind of fight you want to have, the more you will know about the kind of monster that you need to design. If you want some guidance on monster tactics, Keith Ammann over at The Monsters Know What They’re Doing has done more writing on the habits and instincts of different monsters than most of us will do in several lifetimes.

Once you have a clear picture in your mind of the kind of monster you want to create and the purpose that you need it to serve, ask yourself an important question:

Does A Monster Exist that Serves this Purpose Already?

Since before I launched this blog, my sister has been asking me to put together a guide on homebrewing monsters. The first time that she brought it up, I asked if she had a copy of the Monster Manual. To my complete lack of surprise, she said “no.”

Before you put in the work to create a monster to fit a specific purpose, ask if someone has already created one to do the same thing. If you want to use a race of creatures that traditionally serves the Illithid, for example, the Monster Manual includes both Duergar and Grimlocks. Between the Monster Manual, Volo’s Guide to Monsters, and Mordenkainen’s Tome of Foes, there are literally hundreds of monsters already at your disposal in the source books. If you want to expand your search even further, you could invest in some of the compendiums put out by independent designers and publishers on The DM’s Guild and DriveThruRPG. Like most independently-published sources, your mileage may vary, but there are plenty of wonderful and inspired creators working in those spaces who you can support and draw ideas from.

If indeed there is no monster that fills the specific niche that you want—or you want to go ahead and create a new one anyway—the next question gets a little more concrete.

How Many Do You Want There to Be?

At the end of the movie 300, Dilios says to his men: “The enemy outnumber us a paltry three to one. Good odds for any Greek!”

Perhaps this is true for the Spartans, but for most creatures in the Monster Manual, getting outnumbered by your players means a swift and merciless death. In an interview on DM’s Deep Dive, Jeremy Crawford, one of the lead designers of Dungeons and Dragons, said that creatures that don’t have legendary actions are not designed to be encountered alone.

This makes sense when you break it down. Most creatures can only take one action per round. Even if they are making three attacks with that action, they cannot match a party of four that is focusing entirely on it. Unless the threat is far beyond what the party can handle, a single creature attacking once a round is going to get beaten down faster than Kurt Russell at the end of Death Proof.

You may think you can alleviate this problem by increasing the hit points or armor class of the monster in question. That can work, but only to a point. Increasing hit points or armor class, when used judiciously, can make a fight more challenging, but too much makes the creature so hearty that the fight becomes tedious. Beyond a certain point, hacking away at a sack of hit points just gets boring, and the combat drags on forever.

The other problem with this tactic is it doesn’t add to the power or the flexibility of your creature. You’re still only taking one action a turn if you have 20 hit points or 200. This isn’t a problem if your players are encountering six of your custom creatures, but if it’s just one, you’re going to want some way to keep the fight unpredictable and keep the pace of combat up. Which leads me to my next question:

Does it have Special Actions?

Special actions give your creature some much-needed flexibility when facing down a party of adventurers while simultaneously increasing its power level. A single creature facing down an adventuring party is going to need them. They will allow your monster to take some kind of direct or indirect action outside of their own turn.

Powerful creatures in the standard rules have both Legendary Actions and Lair Actions available to them. These are fairly self-explanatory, and the Monster Manual has concise explanations of both on page 11. The biggest difference is that legendary actions are taken by the creature themselves outside of their normal turn, while lair actions are thematic or environmental effects that happen at a set point each round.

Another possible solution is to create an action-oriented monster. This is an idea that Matt Colville developed fairly recently, and he does a good job of explaining it in this video. An action-oriented monster has a specific action that it takes at a predetermined point in each round of combat. In this way, it’s a mix of lair actions and legendary actions; they only happen once per round, but the creature is the one instigating them.

These first four questions are focused on how you want the fight to progress. But the last question asks what happens when the fight is over.

What is the Reward for Defeating It?

At the end of most any fight, you’re going to have a dead creature—and perhaps a couple of dead party members—on your hands. It’s important to think about how you are going to reward the players for defeating your custom monster; few things are more disappointing than realizing that a fight happened for no reason at all.

This doesn’t mean that you have to reward your players with a massive amount of treasure—though if they’re fighting a dragon, that may be expected. Sometimes the “reward” for killing a monster is being able to move forward in the dungeon, the start or culmination of a story line, or something that the players know or suspect will lead to material gain in the future. This is informed in large part by the kind of creature that you’ve made. A creature that doesn’t wear clothes or wield a weapon, like a roper, isn’t likely to have magic items for the players to collect, whereas a vampire or lich almost certainly would. A fire giant might be guarding an important prisoner, but two goblins might just be guarding a door. Think about what makes thematic sense given your creature and your adventure, and plan accordingly.

Once you’ve answered these questions, you won’t wind up with a finished creature, but you’ll have a clearer picture in your head of what it is, how you want it to behave, and how difficult you want it to be. This will make your life that much easier when you are sitting down to figure out the mechanical elements like resistances, immunities, and hit dice. Hopefully, this will shake some of the paralysis of choice and replace it with the clarity of vision.

The rest is up to you.

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