Fiendish Forge (5e) - Evolved Combat, Monstrous Crafting

Created by Io Publishing

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Latest Updates from Our Project:

Fiendish Forge: August 2025 Update
6 months ago – Wed, Sep 03, 2025 at 05:46:19 PM

Hi everyone!  Brett here with your monthly update on Fiendish Forge!

Progress Report:

Here is where we are at:

Writing: 90%
Design: 71%
Art: 97%
Total: 86%

New calculations for Elites/Bosses. Removal of Superboss. Added Underling.

You may notice our Design and Total % went down. This is because, after reviewing the data, I decided to reformulate Elite and Boss CR with a newer system. This means redoing every stat block in the book. Fortunately, with new systems in place, this should be feasible, especially while our art is finishing up. We've got some really cool stuff cooking from the previous month, and I think you guys will appreciate the extra time.

I will say with the new calculations, I really like the direction of all the creatures. It feels more balanced to the previous iterations that should connect well with 5e. In addition, the new sytem allows for more structure when it comes to creating your own creatures. New playtests will be coming soon this month to show off these changes, but internally, the stats feel good.

Superboss CR was removed as it troublesome. Since every GM has a different opinion of what a Superboss feels like, it led to some conflict between making a Superboss not challenging enough, to making it so powerful it was wiping parties. Ultimately felt that the removal of such a ranking was better off.

With that, I created an Underling CR! The idea with Underlings is that it should have the difficulty of 1 Player Character, allowing you to easily create a group of Underlings whose CR matches the party level. It's with my hope that GMs will be able to create encounters with ease with this new CR. 


Phase Turns are BACK and updated! (now Phase Actions)

After testing with the Legendary Action system, I got a lot of folks who were disappointed that Phase Turns were not part of creatures any more. Ultimately I was worried about multiple turns, and when effects were suppose to end. After some though and testing, I decided to combine the idea of Legendary Actions, but in an initiative order.  Effectively, this hybrid are called Phase Actions, and will include rules on how to add Phase Actions to the initiative count correctly. Unlike Phase Turns, which had a category of the type of turn, and what precise actions were taken (in which you'd have to reference in another section) - all the information for Phase Actions are right there *in* the action.  They are still actions, which means they cannot be taken when Incapacitated (much like Legendary Actions), and now we are including a Phase Action that is the turn of the creature itself, in which you would take the creature's turn as normal.  This is where all "Beginning/End of Turn" effects take place, so I'm hoping this solution will be elegant while keeping to the spirit of the previous Phase Combat.

This system would work here using an existing creature from 5e.

Adult Green Dragon (non Lair)
An Adult Green Dragon has 3 different Legendary Actions that we can easily convert into Phase Actions. Because the Green Dragon has an Initiative score of 11, we will have their turn take place on Initiative 21.  If there are 2 Phase Actions along with the Turn, I recommend adding/subtracting 10 from the Initiative count to place those Phase Actions into place. However, since there are 3 (4 in a Lair), I recommend adding/subtracting 5 - making the Phase Actions look like this in Initiative.

  • Dragon's Turn (21 - Turn). The Adult Green Dragon takes their turn as normal.
  • Mind Invasion (16). The dragon uses Spellcasting to cast Mind Spike (level 3 version).
  • Noxious Miasma (11). Constitution Saving Throw: DC 17, each creature in a 20-foot-radius Sphere centered on a point the dragon can see within 90 feet. Failure: 7 (2d6) Poison damage, and the target takes a −2 penalty to AC until the end of its next turn. Failure or Success: The dragon can’t take this action again until the start of its next turn.
  • Pounce (6). The dragon moves up to half its Speed, and it makes one Rend attack.

New Action Type: Burst Actions

Much like Legendary Actions, these Burst Actions allow a creature to do a 1/Encounter action at the end of another creature's turn. This allows the combat to stay fresh with new things continuously happening in the encounter.  Burst Actions have their own damage calculation, meaning they don't take away from the damage a creature is suppose to do during a battle (thus "Burst") - allowing a GM to spike the difficulty as necessary.  When a Burst Action is taken, another Burst Action cannot be taken until the end of the creature's turn.

Legendary Resistance Redux

Once again, we're changing up how Legendary Resistances work. Creatures with Legendary Resistances has a number of uses that they can do it with. However, the Legendary Resistance now costs something to the creature. Originally this was a Legendary Action use, but this can now alternate depending on the creature. Some creatures may activate Legendary Resistance by skipping a Phase Action, while others may activate it by taking damage inflicted upon themselves. I've been finding this system a great way for players to feel like their efforts are being rewarded, even if a Legendary Resistance is used. 

Playtests soon!

I have a lot of life changes happening this month (including a big move), along with some work events I'm attending. However, I'll do my best to get a playtest scheduled for you guys! Be sure to sign up over at our discord. https://discord.gg/e9RCf8bFke 

Brett

Fiendish Forge: July 2025 Update
7 months ago – Thu, Jul 31, 2025 at 08:01:40 AM

Hi everyone!  Brett here with your monthly update on Fiendish Forge!

Progress Report:

Here is where we are at:

Writing: 89%
Design: 87%
Art: 93%
Total: 90%

REVIEWED: 14%
VTT: 2%

Superboss Testing

This month has been all about the Superboss testing, and answering the question - What is a Superboss?  Is it a creature with even more hit points? Does it deal more damage?  Complex mechanics? We've discovered it's a combination of it all, but not entirely focused on one thing.  Confusing, I know.

Superbosses, much like other creatures, need to tell a story while still being threatening enough to hold their own. They should be their isolated encounter, including spawn management, and solutions that must be prepared for outside combat before engaging. They should stand above every other encounter as a penultimate story point, a creature lurking in the background now finally ready to be involved.

Or at least that's what we've discovered so far. Playtesting continues on our Io Publishing server.
https://discord.gg/e9RCf8bFke 

90%!!

We are approaching the finish line regarding all the art and design. I'm hoping that over the next couple of months, we'll flesh out the monster creation rules for folks who want to make their own. We have some artists out of commission for the summer, which has slowed our art production - but hoping to continue to pick up the pace as time goes on.

CR 10 and above:

We have a great handle on CR 10 and below creatures, but we are finding that those above 10 are a bit more challenging to balance. Because of the way 5e is made and the numbers involved, we're finding parties having vastly different experiences depending on what kind of team is being made. I hope to include a "difficulty slider" in optional rules, allowing you to make an encounter more or less challenging depending on the type of party you're running. Still plenty of work to do, and playtesting will continue to help us flesh this out.

More Playtests and Previews Coming!

As I flesh out these creatures, there will be more playtests, although I am approaching the point where I've received all the necessary data.  Be sure to join.  https://discord.gg/e9RCf8bFke 


Thank you!

Thank you for your continued support as we develop Fiendish Forge! Until next month!

Brett


Fiendish Forge: June 2025 Update
8 months ago – Wed, Jul 02, 2025 at 09:50:07 AM

Hi everyone!  Brett here with your monthly update on Fiendish Forge!

Progress Report:

Here is where we are at:

Writing: 90%
Design: 80%
Art: 90%
Total: 86%

REVIEWED: 6%

Reviewed?

We've made enough progress to be in the Review stage! We're reviewing each monster entry, ensuring everything is documented correctly and free of grammar/spelling errors.  We're also redesigning our stat blocks with our new 2024 Stat Block Design - and adjusting some numbers to align with 2024 5e.

New Stat Block

I've been working hard to get a new stat block to align with 2024 5e's design. For the most part, I've enjoyed the latest design in the 2024 version of 5e, so I went ahead and redesigned our stat block to be more in line. In addition, I've taken inspiration from earlier versions of stat blocks, like 4e, to help present information necessary for GMs while condensing space on the stat block itself.  This has led to a ton of page space, allowing me to add more stat blocks and even lore entries onto the page.



Monster Making Mechanics

I've been frustrated at the lack of monster-making mechanics in the newest version of 5e - and while you can still utilize 2014's rulesets, some changes have been made in 2024 where you'll see particular creatures don't have the same calculations as their 2014 counterparts.  I've been using Blog of Holding's findings to make these creatures with solid success. I have expanded the system to allow for more precise adjustments, including traits presented in 2014. As I continue to work on this and fine-tune it with Fiendish Forge, I'm confident that the monsters in our book will be compatible with 2024 5e's creatures.

More to the point, initially, we would have mechanics in place to make your own Elite and Boss CR creatures. In addition, we're including a new type of CR - Superboss - for those penultimate battles in your campaigns. I also hope to have standard monster-making mechanics in Fiendish Forge to compensate for what was not included in 2024! Right now, I'm working on a system that will make it easy for you, the GM, to create monsters quickly.  Even with 2014's rulesets, it was very complicated and easy to make mistakes when making monsters. Blog of Holding has a quick and easy ruleset if you're just looking for something fast. The system I'm designing will enable you to make something even more detailed with Monster Points (MP). You start with a set number of MP to increase a creature's stats above their standard limit, or even acquire specific traits such as Pack Tactics, or our new Legendary Resistance system. However, you can gain more MP by lowering a creature's stats below their standard limits, allowing you to do something, for example, have a creature with low AC but more HP. This system will enable you to fine-tune your monster the way you want it with an easy step-by-step process, and also ensure everything is correct by keeping track of the MP you're spending. I've been using it internally and it's been working great - allowing me to save a bunch of time on making new monsters and quickly adjust monsters we've already made for 2014 into 2024. I hope you're looking forward to it!


 

More Playtests and Previews Coming!

As I flesh out these creatures, there will be more playtests, although I am approaching the point where I've received all the necessary data. Rest assured, there will also be more previews shown, which is happening over at our IO Publishing Discord!  Be sure to join.  https://discord.gg/e9RCf8bFke 
 

Thank you!

Thank you for your continued support as we develop Fiendish Forge! Until next month!

Brett


Fiendish Forge: May 2025 Update
9 months ago – Sun, Jun 01, 2025 at 01:19:11 PM

Hi everyone!  Brett here with your monthly update on Fiendish Forge!

Progress Report:

Here is where we are at:

Writing: 87%
Design: 74%
Art: 86%
Total: 82%

Design Test, Reworks, ReReWorks, and having the "Finger on the Pulse"

As we continue developing art for the book, I've been experimenting extensively with the current system. With SRD 5.2 out and able to create for 2024 5e Content, I've been reworking stat blocks to align with 2024 5e's Design.  Fortunately, the changes made in 2024 are now more in line with how we were designing our creatures (I've heard that my finger is on the pulse MULTIPLE times to the point it's driving me  up the wall).  However, because 2024 is embracing more cinematic combat (such as Legendary Actions with Move being a part of them) - I figured we'd also embrace more the 2024 side of 5e. 

Unfortunately, WotC has decided to withhold information on how to create creatures in 5e 2024 systems.  Fortunately, the community has filled in, and started to reverse engineer the process.  In the past few months, the Blog of Holding has been working on a breakdown of how 2024 5e now makes its monsters - and once again - it seems 5e 2024 has taken a page out of our book - making Legnedary Creatures more lethal in Damage stats (but strangely, not increasing their hit points). However, since this design philosophy seems to have taken hold, we're also reworking a little bit how we're handling some of our systems.

Phase Combat becomes Phase Encounters

One of the biggest challenges with Phase Combat is the Phase Turns, which have led to much inquisition about how these additional turns are handled. We continue to add rules to solve these issues as they arise, but I've felt this approach starts to burden the system with these additions when simpler solutions are on the table.  That's why we're returning to "Legendary Actions" and "Legendary Resistance" as 5e has it, with some modifications of our own.

  • A new resource: Legendary Points (LP)
  • Legendary Actions cost LP to activate.
  • Legendary Actions do more than a single action - which may have the creature move or take other actions (such as Dodge, Disengage, etc)
  • Legendary Resistance uses the SAME resource to activate, meaning if a creature decides to use Legendary Resistance, they are typically taking away from their Legendary Actions (unless a creature is more defensive with additional LP). Legendary Resistance can also be used to end an ongoing condition.
  • Legendary Actions are highly recommended to be taken in order. This allows Legendary Actions to sort of build upon themselves.  

These Legendary Actions are also a part of "Phases" where you can find the Legendary Actions to take.  Phases present a ruleset on how to run the Phase, including when a Phase Advances (or Reverts in some cases).  We can also introduce Transition Phases - sort of an intermission mid-combat, where there may be some sort of trial the party has to overcome to avoid consequences before advancing to the next Phase.

We'll be playtesting this during the month of June, so be sure to join our Discord and sign up for our Playtests if you haven't done so already. I've got some more accessible Phase Encounters for test, as well as some complex Phase Encounters (such as the Sprite Mother) which features a bunch of new mechanics familiar to MMO Veterans. Stay tuned for that announcement!

Our Io Publishing Discord Server: https://discord.gg/e9RCf8bFke


Elite, Bosses, and Superbosses

We will be playtesting many of these values to see if any adjustments need to be made for the encounter's sake, and we're also introducing a "Superboss" category for creatures.  Be forewarned that you won't see many Superbosses in the book (right now, we only have one confirmed - the Astral Tarrasque) - but I wanted to introduce the option.

  • Standard creatures have Standard HP and Damage.
  • Elite creatures have 50% more HP and deal 25% more Damage.
  • Boss creatures have 100% more HP and deal 50% more Damage.
  • Superboss creatures have 200% more HP, and deal 100% more Damage.


Art Preview

I want to start showing art pieces that our art team has worked on to get you guys excited. I was initially thinking about holding these pieces until the book's release, but I'm too excited to wait. This piece is the Vampire Lord - which transforms into a Demon when Bloodied!



Thank you!

Thank you for your continued support as we develop Fiendish Forge!  We will have more to show off very soon!
Brett

Fiendish Forge: April 2025 Update
10 months ago – Thu, May 01, 2025 at 08:09:21 AM

Hi everyone!  Brett here with your monthly update on Fiendish Forge!
We continue to work on the book and make some progress. Unfortunately, I had a complete computer failure (discovered it was a bad CPU), which slowed things down a little bit. Fortunately, no work was lost, and we have since resumed work!

With that, I'm very excited to share our Progress Report!

Progress Report:

Here is where we are at:

Writing: 84%
Design: 69%
Art: 77%
Total: 77%

Creature Art COMPLETE

We have completed all of the Creature art! This means every creature's art piece is done! We're also 88% complete with all of our Quest Art, and are chipping away at Materials/Magic Items art, which will take a bit more time.

SRD 5.2 is now out on the Creative Commons!

One of our bigger roadblocks was the fate of SRD 5.2, which allows us to make content and support for 2024 5e.  WotC has just released this out on the Creative Commons with the same terms as SRD 5.1 - so we can safely say that this book is both 2014 and 2024 5e Compatible!

Tariff Concerns and Future Production

We still have a while before we can begin the physical production of Fiendish Forge. We manufactured WSD:Fishing in China, so these new imposed tariffs (now at 145%) may cause some issues down the road.

Fortunately, we're working with our manufacturing partner to figure out the best course of action to produce and import our products into the country affordably, including working with different countries. Rest assured, we will find the most affordable way to make our products while maintaining a high level of quality. 

We have no current announcements on how this will affect shipping rates since many changes are expected over the next few months. If this current climate persists, some options may include covering the increased costs ourselves and increasing shipping rates to our backers. While I hope it does not come to that, we will try to find an amicable solution to minimize the increased production costs and any increased costs to our backers. Right now, it's just too soon to tell, so stay tuned for future announcements.

Thank you!

Thank you for your continued support as we develop Fiendish Forge!  We will have more to show off very soon!
Brett