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How to Create an Epic Monster
More than a few people have commented on how some of the high-level Fifth Edition monsters can be somewhat lacking. For example, everyone’s favorite city-crushing turtle monster, the tarrasque, leaves a lot to be desired in its Fifth Edition form. This article goes into detail on how to create epic, multi-component creatures for your Fifth Edition campaigns.
The Limitations of CR 30
As a CR 30 monster in Fifth Edition, a creature can only have so much for its stats and ability scores. Looking at the Monster Statistics by Challenge Rating table (DMG), a CR 30 monster has the equivalent of an AC 19, 806 – 850 hit points, a +14 to hit (or DC 23 save), and deals 303 – 320 damage per turn.
Are those numbers insane? Totally. But for a completely rested, carefully equipped and prepared party of 20th-level heroes, that’s just another day at work.
Referencing the Epic Solo Monster Challenge Rating table, we know that a group of seven 12th-level characters can go toe-to-toe against a CR 30 creature (with enough advanced notice, of course). In fact, a group of seven 12th-level characters can reasonably take on 280,000 adjusted XP per day according to the Adventuring Day XP table (DMG), almost twice as much provided by a single CR 30 creature.
In fact, such an encounter could be two monsters of CR 29, three CR 24s, four CR 23s, five CR 21s, six CR 21s, seven CR 18s, eight CR 17s, nine CR 16s, ten CR 15s, and so on.
Creating One Monster from Many
Okay, since we understand the basics of epic encounters, it’s simply a matter of creating a single, devastating monster. And the best way to do this is to take the monster and make it into a bunch of “small monsters.” Thankfully, the recently released “of ships and the sea” rules for Fifth Edition gives us the perfect blueprint for doing just that.
With the ship rules, all of the ships are divided into different components, each of which comprises multiple objects: the hull, control, movement, and weapons. Those ship components can even have special rules described in the stat block. Huge, epic monsters work the same way, especially if you want something that’s bigger than “gargantuan.”
Consider something like Great Cthulhu. Cthulhu has his elephantine body; this is his “hull.” His head controls his body and every other part. He can move by walking or by flying. And for weapons, he’s got tentacles, claws, and a whole bunch of special attacks. Instead of slapping a CR 30 on everyone’s favorite Great Old One and calling it a day, we can take Cthulhu’s separate components and turn him into an epic challenge.
Building an Epic Challenge on a Budget
If you know the size of the party and the amount of adventuring day XP they can handle, you can use those numbers to reverse engineer the epic monsters. Here is how to come up with that number.
- First, determine the amount of adjusted XP per Day per Character (DMG, chapter 3). Multiply that number by the total number of characters in the party. For example, a party of four 12th-level characters can handle a total of 46,000 adjusted XP per day.
- Next, decide how many components you want your epic monster to have. In the Cthulhu example above, Cthulhu had six components: body, head, claws, feet, wings, and tentacles.
- Treat each component as its own “monster” and determine the challenge rating for each piece using the Enoucnter Difficulty Multipliers table (DMG, chapter 3). Cthulhu has six components, so the encounter multiplier will be x2.
- Divide the total adjusted XP per day by the encounter multiplier and the total number of components. This is the experience points rewarded per component. Since Cthulhu has six components and an encounter multiplier of x2, each component will need to be worth 3,833 experience.
- Pick the components’ challenge rating based on the experience reward. With our Cthulhu example, each component is worth 3,833 unadjusted experience. That’s roughly a CR 8.
- Double-check your math. When dealing with numbers like these, you want to make sure you’re not too far off. A miscalculation can result in a TPK for sure. A CR 9 monster is worth 3,900 XP. Six CR 8 monsters would be worth a total of 23,400 experience. Using the encounter multiplier of x2 for six creatures, that’s a total adjusted encounter XP of 46,800. Divide that four ways, and we have 11,700 adjusted XP per day per character. Perfect for a group of four 12th-level characters.
How to Build Each Component
Now that we have the math out of the way, it’s just a matter of building the creatures. According to the “Creating a Monster” rules (DMG, chapter 9), we know roughly what monster statistics by challenge rating should equal. For example, a CR 8 monster has an AC of 16, 176 – 190 hit points, a +7 attack bonus, and deals 51 – 56 damage per round.
Remember that certain features and abilities such as flying or damage immunities can affect these values.
Here are examples of how to build each component.
Cthulhu’s Basic Stats
First, we need to have Cthulhu’s basic stats. These are the stats that are common for each component. Just like a typical monster stat block, it lists his size, type, ability scores, traits, and features.
Here is a way that I might build out our six CR 8 component Cthulhu’s basic stats.
Next, we to determine Cthulhu’s action allowance. As a multi-component epic threat, Cthulhu will have a mix of regular actions and legendary actions. To avoid confusion, it’s best to put all those elements directly into his stat block. Then, we offer up actions that make sense for him to take, similar to the way ships operate.
This is the language I use for his actions and legendary actions. I’ve given Cthulhu the ability to make up to six attacks per round, three on his turn, and three as legendary actions.
Next, we use Cthulhu’s body to set the biggest target for his challengers. This acts similar to a ship’s hull, establishing the majority of Cthulhu’s hit points and AC. Because the body won’t have any attacks of its own, we’ll need to make the hit points and AC disproportionate to the rest of his form.
The component that controls Cthulhu’s movements is his head. In addition, it acts as a weapon, too, allowing him to make attacks with spells and magical abilities.
Cthulhu’s Movement Components
Now we need a way for our epic Cthulhu challenge to get around town. We’ve given him two such components, detailed below.
Cthulhu’s Main Weapons
In addition to the magical abilities of his head, Cthulhu can make attacks with his claws and his tentacles, as detailed below.
And that’s pretty much it. You now have a massive, unspeakable, eldritch horror stomping around beating up your characters. If they destroy Cthulhu’s head, he can still thrash around with his claws and wings. If they destroy his body, he can still deal damage with his spells and magical effects, but can’t heal himself beyond his regeneration. Good times!
Now that you have rules for creating epic monsters, what sort of horrible creations will you create? Ω
PS I realize that this version of Cthulhu may be seen as somewhat “weak.” If you prefer, consider this a “star spawn.” And for a much tougher Cthulhu, check out https://www.dmdave.com/cthulhu