Combat Encounter Adjustments – What’s Allowed (With Citations!)

Article last updated on 10th November 2021, after the release of the FR FAQ v11.1 which clarified what sources you can draw upon.

As a frequenter of several Adventurers League discord channels, I’ve observed a lot of confusion about adjusting encounters.

Some DMs are afraid to make any adjustments whatsoever for fear of stepping out of line of the Adventurers League rules. Other DMs see the magic words DM Empowerment and assume they can do literally anything. Most of these are benign, but mistaken, but you do hear the occasional horror story.

To make things worse, figuring out the full scope of what exactly is allowed is a maddening exercise. It’s simple enough if you just wanna add or remove monsters. For anything else, you will probably need to cross reference several documents and social media threads, understand the context and chronology of each one, and make a conclusion.

I’m writing this article so you don’t need to do that. Whether you like to do things to the letter, but are too busy to check, or if you really just didn’t know the full scope of DM empowerment, this article is for you. 

I’ve had to make a few decisions of how to interpret each source. The process of this is not easy reading, but here’s a few core assumptions:

  1. Rules and rulings don’t automatically expire with time and are only considered superceded if the document is directly superceded.
    The Season 9 AL DMG is a valid source because no Historic or Masters DMG exists to supercede it. The Season 8 AL DMG is not, because it was directly superceded by the S9 one. The Season 9 FAQ and Content Catalogue are likewise valid sources as no document has superceded them.
  2. Rules with regards to one campaign generally apply to other campaigns unless otherwise stated.

You can add or remove any monster from an encounter as long as it's "thematically appropriate"

Let’s start with the fundamental rule.

Many DMs assume that just because the adventurers league rules prescribe everything from magic items to billable hours, that the monsters are also set in stone. Fortunately, every single AL DMG tells DMs that they are in fact allowed to add or remove any monster from an encounter… so long as it’s thematically appropriate.

What’s “Thematically Appropriate”? A subjective term that’s not within the scope of this article to unpack. Generally, you should identify the significance or use of each encounter to the module, and try to stick to the same conditions.

You may have noticed two things:

  1. Adding and removing monsters also naturally enables swapping monsters.
  2. Those three things already give you a ridiculous amount of control!

If all you wanted to do is make things easier or harder for your party, this rule is more than enough.


DDAL OoW DMG (v1.5), Part 2: Running Adventures, Playing the Dungeonmaster

DDAL Seasonal DMG (v10.0), Part 2: Running Adventures, You’re the Dungeonmaster!

A Historic and Masters DMG does not exist, however, the same rule existed even during Season 9:

DDAL DMG (v9.1), Part 2: Running Adventures, Challenge Your Players

You can use monster statblocks from any Hardcover Book legal for the campaign you're DMing for.

Or as the cool kids call them, Official D&D Book Adventures and Supplements.

Taking monsters from Adventurers League or Community Adventures, what the AL Community informally calls “modules”, is NOT allowed.  This is a group that includes DDEP, DDEX, DDAL, DDAO, CCC, DC module codes.

Currently there are conflicting definitions for which category Guild Adept material counts under, however, the most recent definition (the FAQ v11.1) counts them as Official D&D Book Adventures.

The monsters you’re using need to have entire statblocks. If a monster was adjusted outside of a statblock in an adventure, you can still only use the version in the statblock.

NOTE: This ruling is only in the Forgotten Realms FAQ, so it is not explicit for the Eberron and Mist Hunters campaigns. However, I believe it is a safe to assume that it believes in an analagous way.


DDAL FR FAQ (v11.1), Part 3: Dungeon Master Questions, Substituting Monsters

You can adjust the hit points of a monster up and down within the ranges specified by the hit die.

This was generally true for D&D as a whole, but explicit statements of AL-legality were limited to rulings on Social Media until the Seasonal DMG was released.

The real use of this rule is fudging monster hit points so they die earlier or later as needed.


DDAL Seasonal DMG (v10.0), Part 2: Running Adventures, You’re the Dungeonmaster!

Discord Announcement, Amy D, quoting Travis W, 20th May 2021

For NPC statblocks, you may add racial traits and change their spells

NPCs here are defined not in the normal sense, but as any statblock in the special “NPC” appendices in various books. These statblocks tend to have generic names like “Scout” or “Evoker”.

Currently, the Monster Manual, Volo’s Guide to Monsters, and Eberron: Rising from the Last War possess these appendices (although ERftLW doesn’t call it that).

The Monster Manual explains how you can adjust these statblocks- but of the four possibilities listed there (Change equipment, change spells, add racial traits, add magic items) only two of them are allowed in AL.

DMs are NOT ALLOWED to change the spells or add racial traits for any other statblock. Yes, this means that changing that Lich’s spells is actually not allowed.

What are racial traits in this context? Technically, you need to consult the NPC Features table in Chapter 9 of the Dungeonmaster’s Guide to figure out what to apply, but it’s basically everything a PC of that race would get. Unfortunately, on that table, only races which are in the PHB are described as not affecting CR.

What spells can I change? Look for the class that each NPC is described as being in their spellcasting ability. If they are a wizard, you can only change their spells to other wizard spells and so on.

Note: It is unclear whether the type needs to be “Humanoid (any race)” for you to be allowed to add racial traits. A quandary currently only relevant to the Eberron campaign.


Discord Announcement, Amy Lynn Dzura, quoting Travis Woodall, 20th May 2021

Note: Other sources for this ruling exist, but this is the clearest and most recent one. As someone that has had several arguments with DMs about the confusing phrasing in the old source, I’m super glad this new one was made.

Statblock Adjustments from Certain Sources

There are many recommended adjustments for monsters scattered about various sourcebooks. In general in AL, “variant” and “optional” rules are not allowed, and even modifications which aren’t explicitly framed as optional rules are assumed to be off the table.

However, this section lists a few adjustments which have been greenlit by the admins at some time or another. Whether that bandit captain is now a secret Zariel worshipper or that devil now has acid teeth, these adjustments allow you to spring a few surprises on a party that’s expecting the same-old game.

Diabolical Cults and Demonic Boons from MToF

While I’d personally use these sparingly and only when fiendish influence has already been established by the adventure, these features can pack quite a punch.

Devil Adjustments from Infernal Encounters (Chapter 2)

I’m incredibly puzzled that we’re allowed to use these, but the extra Infernal Warmachine rules are off the table. But there are several incredibly meaty and flavourful options for changing devil statblocks here.


Mordenkainen’s Tome of Foes Primer v1.2

Tweet, Greg Marks, 20th Feb 2020

Is that all?

Although this article provides sources for many of the major questions DMs have regarding allowed combat adjustments, for the sake of brevity I have left out several types of changes which are not usually questioned by DMs or players. This article isn’t exhaustive.

If you have more questions about the sources and their validity, or about other possible adventure encounter changes, you can always ask about it on our Discord channel or PM me directly at @telehax#3409.