5 Tips for Homebrewing Monsters
Homebrewing better 5E monsters with Foe Foundry means prioritizing damage output, using interactive debuffs instead of save-or-suck effects, and eliminating redundant attacks. These five design principles create monsters that are threatening, flavorful, and fun to run at the table.
Opinionated Advice
This article shares my opinionated advice on how I go about designing and creating homebrew monsters. 5E is an open system and there's room for many different styles of monster design. I encourage you to pick and choose what works best for you and your games!
Tired of vanilla monsters that feel like soggy cardboard in combat? Homebrewing monsters in 5E can turn forgettable encounters into memorable moments, if done right. This guide walks you through five practical tips to design custom monsters that hit hard, act smart, and keep players on their toes. Whether you're building from scratch or tweaking existing statblocks, these ideas will help you create monsters that actually matter.
A Monster's Primary Threat Is Its Damage
If you just multiattack with the monster, it should present a challenge in its raw damage output. Abilities should then add interesting flavor, unique mechanics, and other tactical effects on top of the raw damage to make combat exciting.
A classic example of this is the 2014 Mage from the 5E SRD:
The Problem: It has a completely pointless dagger attack that wastes space and detracts from the quality of the statblock. All of the monster's damage and threat is locked into spells, and you have to know which spell to use because there are a bunch of filler spells on the spell list.
The Solution:
Diviner Mage
Summoned with Foe FoundryMedium Humanoid (Wizard)
AC 16 (Arcane Armor) Initiative +2 (12)
HP 91 (14d8 + 28)
Speed 30 ft.
| Mod | Save | ||
|---|---|---|---|
| Str | 10 | +0 | +0 |
| Dex | 14 | +2 | +2 |
| Con | 14 | +2 | +2 |
| Mod | Save | ||
|---|---|---|---|
| Int | 18 | +4 | +7 |
| Wis | 13 | +1 | +4 |
| Cha | 12 | +1 | +1 |
Skills Arcana +7, History +7, Perception +4
Senses Passive Perception 14
Languages Common
CR 6 (2,300 XP; PB +3)
Traits
Portent of Weal and Woe (2/day). When another creature the wizard can see within 60 feet makes a d20 test, the wizard can replace the result of the roll with a 5 or a 15.
Actions
Multiattack. The wizard makes three Time Warp attacks. It may replace two attacks with a use of its Spellcasting.
Time Warp. Ranged Spell Attack: +7 to hit, range 30ft., one target. Hit 15 (2d10 + 4) force damage. On a hit, the target is pushed up to 10 feet horizontally.
Spellcasting. The wizard casts one of the following spells, using Intelligence as the spellcasting ability (spell save DC 15):
2/day each: Detect Magic, Detect ThoughtsȻ, Flyc, Hold Personc (3rd), Arcane Eyec
1/day each: Lightning Bolt, Greater Invisibilityc, Scryingc
Bonus Actions
Overchannel. The the wizard begins to channel vast amounts of power into its next spell. If it begins its next turn with no creature next to it, then the next spell attack it makes that turn that hits a target deals maximum damage.
Misty Step (2/day). The wizard teleports up to 30 feet to an unoccupied space it can see.
Reactions
Protective Magic (2/day). The wizard casts Shield or Counterspell in response to being attacked or being targeted by a spell.
The Foe Foundry statblock has several improvements:
- if you just multiattack, the monster will do plenty of damage
- but, if you want to keep it interesting, you can cast one of its spells. And you'll see there are no filler spells on its spell list
- and the monster has a unique and interesting ability
Monsters Can Be Interesting & Threatening
Foe Foundry monsters often have bonus actions or powerful actions that can replace attacks in the multiattack. This way, your monster will always do something interesting on its turn and still be able to threaten players with damage output.
Let's look at the 2014 Doppelganger from the SRD:
The Problem: the features that make a Doppelganger unique and interesting are its ability to shapeshift and read minds. But, with this statblock these require the Doppelganger to use up its action. So, in order to do something fun and interesting, this monster has to give up doing any damage. Also, its damage output is pitiful. So why would anyone ever run this monster as-is?
The Solution: Read Thoughts and Shapechanger are flavor abilities, and they shouldn't waste the monster's action economy. They should be Bonus Actions or something that triggers automatically without requiring an Action. Also, Read Thoughts should provide some additional mechanical benefit to the Doppelganger.
Let's fix Read Thoughts
Read Thoughts
Bonus Actions
Read Thoughts. The aboleth magically probes the mind of a creature it can see within 30 feet. That creature must make a DC 11 Wisdom saving throw. On a failure, the aboleth can read the target's thoughts as per the Detect Thoughtsc spell. Additionally, when the aboleth hits the target with an attack, it deals an additional 2 (1d4) psychic damage.
Used by Aberrant Cultist Initiate (CR 4)
By making this ability a Bonus Action it no longer competes with the monster's attack, and by tweaking it to have an actual mechanical effect relevant to combat, we can lean more into the flavor of the Doppelganger finding and exploiting the weaknesses of its prey.
Monsters Don't Need Multiple Repetitive Attacks
No more boring french-vanilla "Bite Claw Claw" monsters. These sorts of attacks waste space on the statblock and make it appear like there is more going on in the statblock than there actually is.
Let's look at the 2014 Barbed Devil from the SRD:
The Problem: This monster has 3 attacks, which take up the majority of the statblocks. The attacks don't actually do anything besides slightly different amounts of damage, but you have to roll different numbers of dice and use different damage and attack modifiers for each. Why? It's a complete distraction.
The Solution: Monsters in Foe Foundry have a default attack that will often get attack modifiers added in (such as Weakening Attack or Frightening Attack). Secondary attacks are only added if they actually add something interesting, like the unique mechanic in Nullification Maw.
Nullification Maw
Traits
Nullification Maw. Magical effects, including those produced by spells and magic items but excluding those created by artifacts or deities, are suppressed inside the aboleth's gullet. Any spell slot or charge expended by a creature in the gullet to cast a spell or activate a property of a magic item is wasted. No spell or magical effect that originates outside the aboleth's gullet, except one created by an artifact or a deity, can affect a creature or an object inside the gullet.
Attacks
Swallow. Melee Weapon Attack: +6 to hit, reach 10ft., one target. Hit 19 (6d4 + 4) piercing damage. On a hit, the target must make a DC 14 Dexterity saving throw. On a failure, it is Swallowed. A swallowed creature is Blinded, Restrained, and has total cover against attacks and effects from the outside. It takes 7 (3d4) ongoing acid damage at the start of each of its turns. If the swallowing creature takes 5 damage or more on a single turn from a creature inside it, it must make a DC 15 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures which fall Prone in a space within 10 feet of it. If the swallowing creature dies, the swallowed creature is no longer restrained by it and can escape by using 15 feet of movement, exiting prone. Also see Nullification Maw.
Monsters Should Use Interactive Debuffs
Instead of paralyzing a character, Foe Foundry monsters use new conditions like Weakened, Shocked, Frozen, etc. These conditions take away less player agency and are more interactive than their harsher cousins like Paralyzed and Stunned from the official 5E rules.
The Problem: In the 2014 and 2024 Monster Manual, some monster's challenge rating is balanced around the fact that the monster imposes debilitating conditions like Paralyzed and Stunned. The problem with this design is two-fold:
- If the monster succeeds at stunning or paralyzing a player, they end up losing a turn, which isn't very engaging for that player.
- The ability is super swingy. If no one ever gets stunned, then the monster will be boring. If everyone gets stunned, it will be super deadly.
The Solution: Foe Foundry takes a different approach. Rather than relying on swingy debilitating powers, Foe Foundry monsters have effects that apply interactive debuffs. These effects are typically stapled onto the monster's existing abilities or attacks so they don't detract from the monster's damage output, while the effect itself is not nearly as swingy as paralyzing or stunning a creature.
For example, consider the Toximancer power:
Toximancer
Summoned with Foe FoundryMedium Humanoid (Wizard)
AC 16 (Arcane Armor) Initiative +2 (12)
HP 91 (14d8 + 28)
Speed 30 ft.
| Mod | Save | ||
|---|---|---|---|
| Str | 10 | +0 | +0 |
| Dex | 14 | +2 | +2 |
| Con | 14 | +2 | +2 |
| Mod | Save | ||
|---|---|---|---|
| Int | 18 | +4 | +7 |
| Wis | 13 | +1 | +4 |
| Cha | 12 | +1 | +1 |
Skills Arcana +7, History +7, Perception +4
Senses Passive Perception 14
Languages Common
CR 6 (2,300 XP; PB +3)
Traits
Mindfire (Disease). This creature can inflict the Mindfire disease: The creature's mind becomes feverish. The creature has disadvantage on Intelligence checks and Intelligence saving throws, and the creature behaves as if under the effects of the Confusion spell during combat.
Actions
Multiattack. The wizard makes three Poison Bolt attacks. It may replace two attacks with a use of its Spellcasting.
Poison Bolt. Ranged Spell Attack: +7 to hit, range 30ft., one target. Hit 18 (4d6 + 4) poison damage. On a hit, the target must make a DC 15 Constitution saving throw or become Poisoned until the end of its next turn. On a hit, the target must make a DC 15 Constitution saving throw. On a failure, the target loses 1 hit die and rolls those die and takes that much poison damage. If the target is out of hit die, it is diseased with Mindfire.
Spellcasting. The wizard casts one of the following spells, using Intelligence as the spellcasting ability (spell save DC 15):
1/day each: Acid Arrow (3rd), Cloudkillc, Contagionc
Bonus Actions
Sapping Poison (1/day). Immediately after dealing poison damage to a target that the wizard can see within 60 feet, it causes that target to make a DC 15 Constitution saving throw. On a failed save, the target gains Weakened (save ends at end of turn) until the end of its next turn. A weakened creature deals half damage with its spells and attacks and has disadvantage on Strength ability checks and saving throws.
You Don't Have to Brew by Hand
If you build a statblock by hand, you have to worry about fiddling with statblocks, calculating hit modifiers, and scaling damage to be appropriate to CR.
Foe Foundry takes care of all of that for you with a Monster Generator and Over 600 Powers at your fingertips.
Need a monster for tonight? Get started and summon unforgettable foes instantly, like this Diviner Mage.
Part 2
Four More Tips for Homebrewing continues the series with more tips and tricks for homebrewing monsters.
Frequently Asked Questions
How do I balance damage for a homebrew 5E monster?
Use the Monster Stats by CR table from the Foe Foundry Design Guide. Choose your target CR first, then assign HP, AC, and damage per round based on the baseline values for that CR.
Should homebrew monsters have multiple attack types?
Only if each attack does something mechanically different. Avoid "Bite, Claw, Claw" monsters where attacks are functionally identical. Instead, use one primary attack with interesting modifiers or effects.
What are interactive debuffs in 5E?
Interactive debuffs like Dazed, Frozen, or Weakened create tactical choices without removing player agency. Unlike Stunned or Paralyzed, they let players stay engaged by choosing between fighting at reduced effectiveness or using resources to remove the condition.
Can I use Foe Foundry powers in my homebrew monsters?
Yes! All Foe Foundry powers are designed to be modular and scalable to any CR. Browse the power library to find abilities that fit your monster concept, and they'll automatically scale to your chosen CR.
How do I make homebrew monsters interesting without making them overpowered?
Give them bonus actions or abilities that replace attacks in their multiattack, rather than adding extra actions on top. This lets them do interesting things while maintaining balanced action economy and damage output.