D&D 5E Encounter Building - Building a Better Model


Recently I have heard the challenge that a better encounter building model cannot be done in 5e, it would be completely unwieldy and just cannot take into account the various complexities of 5e play.

Against my better judgement (why do I torture myself), I decided to give it a shot. And so I put myself in front of the firing squad!

MOST IMPORTANT NOTE!!!: All of the numbers provided here are flat out wrong. None of them have been tested or tuned to any mathematical rigor. The numbers are simple placeholders, the construct of the model is what we are looking at and assessing.

In other words, there is 0 point to say "your multiplier in chart X looks too high" or "I think the total XP for X is just too low". If you think the numbers are wrong, its because they are. Feedback should be around structure. Does the process seem reasonable, is it still reasonably simple, does it seem to incorporate the extra features in a solid way?

Goals and Notes
GOAL: Adjust the current encounter system by accounting for additional and common factors that effect encounter difficulty, while only promoting a minor increase in complexity. The system must remains fairly simple and usable. Ultimately the system still relies on DM judgement to adjust, but provides better guidelines towards that end.

NR: I use this acronym (“No Rewrite”) for sections that are the same as the original system, and I choose not to rewrite them to save space and reading.

Main Inclusions: In general, I am attempting to include these factors into the model.

1) Party "Style": While we can't account for every possible combination of players and classes, we can at least account for some basic styles of play. Do groups like to rush into melee, hang back and fire from range, blast everything with fireballs, start out with control spells and status effects, ambush everything etc. Likewise we can provide such designations to our monsters to help us get a basic idea of how a fight is likely to go.
2) Magic Items: Magic Items strengthen players, and so should be taken into account in some form or fashion.
3) Terrain: Again, there are several "terrain styles" commonly seen in dnd combat that we can account for at a basic level.
4) Player Number: While this is accounted for in the model, there are certain monster types that magnify or discount party number, and we want to give this some attention.
5) Number of Encounters: Ah the big one, some would say the holy grail. For parties that prefer fewer numbers of encounters per day, can we reasonably account for thin encounter design?

Building an Encounter (Basic Steps)
Follow these steps to determine the difficulty level of your encounters.
  • Determine the Effective Character Level of each character in the party.
  • Set the XP thresholds for your party, based on the Resource Pace you want to set.
  • Total the Monster’s XP.
  • Determine the Style of your party and the enemy.
  • Adjust the Monster XP by the Encounter Modifier.
  • Adjust the Monster XP by Monster Number
Determine a Character’s Effective Level
To gauge a character’s strength, we start with their character level, and then modify it based on factors.

1. Optimization Rank: Some players optimize their characters for combat, while others have trouble even remembering the combat rules. Use the following chart to help adjust a character based on its player’s proficiency with combat mechanics.

Effective Character Level Modifier (Optimization Rank)
Character Base Level
*If the character is a long rest type spellcaster (wizard, sorcerer, cleric, bard), add an additional +1 level.

Roleplay: This player doesn’t care about combat, and will often build characters that have anti-optimizations in the pursuit of roleplay. Example might be a wizard with a low Int score, or a fighter who never attacks unless they are actually wounded in combat.

Casual: This player will generally build a normal character but doesn’t have a great grasp of the rules and won’t make the best decisions.

Standard: Player enjoys combat, and knows the rules reasonable well. Will have decent tactics in combat and build a character with combat as a factor. Use standard if you are unfamiliar with a player.

Optimized: This player lives for combat. Their character is likely to be heavily optimized or even min/maxed for combat. Player will always make the best tactical decisions.

Ex: A 7th level character built and run by a Roleplay rank player has a -1 effective level adjustment. Once the character is 11th level, the adjustment changes to a -2.

2. Magic Items
: Further adjust a character’s level based on the amount of magic items they use. Add up all modifiers for multiple items, and then round down.

Ignore Non-Combat Items: Many magic items have strong properties, but have no real impact to a combat encounter. Ignore these items for the purpose of level adjustment.

Multiple Magic Items: Only add in items if they are all expected to be usable in a fight. For example, a fighter with two magic greatswords can only use one at a time, so only count the strongest one. However, magic armor and a magic shield would both get used together and should both be counted.

Effective Character Level Adjustment (Magic Items)

Character Base Level
Very Rare+2+2+1.5+1.5
*An uncommon weapon that counts as magic for the purpose of bypassing monster resistance to non-magic weapons is treated as rare.

The 5th level Rule: 5th level is a special threshold, representing a major increase in character strength and skill. It also represents a major increase in the threats a character can take on.

After you have applied your level adjustments, if the adjustment increases a character to or beyond 5th level (or drops a character below 5th level), half the total modifier.

Ex: A 5th level character is run by a Roleplay rank player with no magic items. Level adjustment is 5 -1 (roleplay rank) = 4th level. Because this crosses the 5th level threshold, the DM halfs the modifier to a -1/2….which rounds to 0. Effective Level: 5 - 0 = 5.

A 4th level character is run by an Optimized Rank player. In addition they have a +1 sword (uncommon) and +2 armor (rare). A +1 sword can bypass resistance to non-magic weapons so we treat it as a rare item. Modifiers are +1 for rank, +1 for a rare, and +1 for another rare (+3 total). This puts the character at 7, which crosses the 5th level threshold. We half the bonus to +1.5, round down to 1. Effective level: 4+1 = 5.

An 11th level character is run by a Casual rank player. They possess a “Singing Sword”, a funny talking sword with no bonuses, and +3 (legendary) armor. We ignore the singing sword as it does not affect combat. Our modifiers are -1 (casual) + 2 (legendary item) = +1. Effectively level = 11+1 =12.

Set the Party XP Threshold

(NR), Medium. (NR), Hard. (NR), Deadly. (NR)

Lethal. This combat is meant to push a party to its limit. A death is a reasonable expectation, and the death of the entire party is a possibility. DMs should be very cautious when using this level of difficulty, and is meant only for parties that wish to be truly tested.

Resource Pace
The pace at which players expend their resources determines how many encounters they can reasonable handle in a given day, as well as how tough those encounters can be.

Standard: Standard parties are generally frugal with their resources, often saving their biggest abilities only when needed. They can handle about 6-8 medium encounters per day.

Nova: Parties that nova exhaust resources quickly. They generally consume resources 2x as quickly, and can handle 3-4 encounters per day. Parties do not normally Nova against easy fights, so those are not included.

Supernova: A party that goes all out in every fight, using their strongest resources as quickly as possible, generally consume resources 4x as fast as standard and can only handle 1-2 encounters in a day. Parties will generally only supernova against Hard or higher fights, so only those are included.

XP Thresholds by Character Level​

Designer Note: I only included a few levels as an example. Note that as the levels go up I am increasing the Nova and Supernova levels higher and higher, to account for the additional resources of higher level characters.


Total the Monster’s XP (NR)
Determine the Style of the Party and the Enemy

Style: Every party (whether its composed of PCs or Monsters) is a unique combination of abilities. However, most party’s have a default “style” that they like to approach combat and generally are built around.

Melee: The group has several front liners, who want to get in close and are strongest in melee. Ex: A 4 person party of a Paladin, Cleric, Great Weapon Fighter, and Rogue.

Range: This group prefers to stay back and fire from afar, often letting one tank character hold back the enemy. Ex: A bow ranger and fighter, a wizard, and a tanky barbarian.

Artillery: This group likes to blow it up, often using area effect spells to deliver destruction from afar. Ex: An Evocation Wizard, a fire sorcerer, a rogue, and a cleric.

Controller: This group relies on status effects or terrain changing spells to hinder and isolate the enemy. Ex: A stun focused monk, a Enchantment Wizard, a rogue, and a grapple focused fighter.

Balanced: The party does a bit of everything, and has no real focus. Ex. A sword/shield fighter, a wizard, a bow rogue, and a bard that is equal at range and melee. If you are unsure as to the party’s style, use Balanced as your baseline.

Adjusting style over time: As you become more experienced with your group (and they become more experienced with their charcters), you may reassess what style they use. Or they may use different styles at different times. Ex: You know that your evocation wizard just loves to cut lose with fireballs at the first opportunity, often running out after 1-2 encounters and then relying on single target range spells. So for encounters 1 and 2, you may treat your party as an Artillery group. However, by encounter 3 you may adjust them to a Range group.

Adjust the Monster XP by the Encounter Modifier
Encounter Features: Review the options below and determine which feature (or more than one if applicable) applies to your encounter.

Standard: Generally encounters starting between 60 to 150 feet, with no notable features other than the enemy itself.

Long Range (LR): The encounter begins where both sides are 150 feet or farther apart. Often appropriate for open outdoor encounters.

Tight Space (TS): Encounter begins with 60 feet or less, often restricting players from moving farther part either through physical barriers. A typical closed dungeon room is one example.

Narrow Chokepoint (NC): One side is forced to attack or through a 5 or 10 foot chokepoint. A party trying to fight an enemy in a tight mountain pass or through a dungeon door.

Limited Visibility (LV): Conditions that greatly hinder sight, often forcing people to be close together to avoid large penalties. A darkness filled room is an example.

Difficult Terrain (DT): A large or a key portion of the encounter has terrain that limits movement. An outdoor swamp is a good example.

Heavy Cover (HC): Cover is plentiful and can provide major defense bonuses. A thick forest is a good example.

Lethal Terrain (LT): Terrain that can damage characters. A platform up in the air, or a region with a large spiked pit trap are examples.

Ambush (A): This group is likely to get surprise over another group. A group of kobolds preparing to jump out of the darkness and attack.

Encounter Modifiers
  • Determine the Encounter Modifier for the Enemy and Players sides based on the Encounter Types chosen (see chart below)
  • Overall Encounter Modifier (OEM) = Enemy Encounter Modifier – Player Encounter Modifier
  • Modify the Monster XP by the modifier given in the chart below.

XP Modifier for OEM

Ex: A party of a barbarian, a melee fighter, a cleric, and a wizard are encountering a group of 3 Flameskulls with one guardian ghoul down a long narrow hallway. The hallway is filled with ghostly apparitions that slow down living creatures.

The base XP of the enemy is: 3500. The DM determines that the enemy is mostly an Artillery style due to the fireball of the flameskulls. For their party, who generally likes to rush into combat, the DM considers a Melee Style.

Since this is a Narrow Choke encounter, the enemy has a +3 modifier for an Artillery style. Meanwhile our poor melee party has a -2, due to the difficulties getting into melee in a tight choke. The encounter is also a Difficult Terrain encounter, due to the slow effect. The enemy gains an additional +2 modifier for a total of +5, while our party receives an additional -1, for a total of -3.

Our overall encounter modifiers = 5 – (-3) = 8. Consulting the chart, that is an XP modifier of 1.8.

Our Encounter XP is now 3500 x 1.8 = 6300. This particularly terrain has made those flameskulls very powerful!

Adjust the Monster XP by the Player Number
After you have adjusted the monster XP by your encounter modifier, modify the number a second time by the number of Monsters and players, noted in the chart below.

Monster Number
Player Number
*Against Controller style enemies, add an additional +1 to the modifier.
&Against Artillery style enemies, add an additional +.5 to the modifier.

Putting in all Together, A Full Example
DM Bob is finishing up a major arc in his campaign, and he wants to create a few really nasty encounters as they encounter the BBEG. His party is:

  • A 5th level Barbarian played by the real roleplayer of the group. The barbarian is not optimized at all, but is always fun to see in action. They have a special rare armor.
  • A 5th level Dragon Sorceror played by a solid and standard player. They have a mirror that can see through magical disguises.
  • A 5th level Light Cleric by another standard player. They possess a pair of dual swords, one with a bonus against evil, and the other against good (both uncommon). They aren’t considered a full +1 bonus, but they do count as magic weapons for bypassing monster resistance.
  • A 5th level rogue, played at high optimization. The rogue has a headband that gives him advantage on all insight checks.
  • A 5th level Champion Fighter, played by a casual person. No magic items.
  • A 4th level Bard, who joined the game late and is a level behind. Its run by one of his oldest and most veteran players, and is quite optimal. Has a +1 sword (to help compensate for the lower level).
Effective Character Level
  • Barbarian: 5 -1 (roleplay rank) + 1 (rare item) = 5
  • Sorc: 5 +0 (standard rank) +0 (magic) = 5. While the mirror is a neat item in social scenarios, its not going to be much help on the adventurer, and so we are not adjusting for it.
  • Cleric: 5 +0 (standard rank) + 1 (rare) = 6. The uncommon swords bypass monster resistance to non-magic weapons, which automatically makes them rare. However, the cleric generally only uses one the evil bane sword, the good sword only comes up in very rare circumstances, so we won’t count.
  • Rogue: 5 + 1 (optimized rank) + 0 (no magic) = 6. The headband is an amazing item outside of combat, but is unlikely to be a combat factor and is not counted.
  • Fighter: 5 -1 (casual) +0 (no magic) = 4. Normally the adjustment would drop the fighter to level 4. However, because we dropped below 5th, the “5th level rule” applies. We drop the penalty to -1/2 (rounds to 0). So the fighter is actually 5 – 0 = 5.
  • Bard: 4 + 1 (optimized) + 1 (rare) = 6. The +1 sword counts as a rare due to its ability to bypass monster resistances. This puts the bard up to a 6. However, as this crossed 5th level ,the “5th level rule” applies. The bonus is halved to 1, and so its 4 + 1 = 5.
Player XP Thresholds

4 characters with ECL of 5 + 2 ECL of 6.

Designer Note: Apologies I made a math error below, and used 5 ECL 5s and 1 ECL 6. I'll try to correct the mistake later, but for the example the numbers are fine.

Standard Pace (Green entries in the table)
Easy = 250 x 5 + 300 = 1550, Medium = 500 x 5 + 600 = 3100, Hard = 5 x 750 + 900 = 4650, Deadly = 1100 x5 + 1400 = 6900, Lethal = 2200 x5 + 2800 = 13,800

Nova Pace (Blue entries, math not shown)
Medium = 4650, Hard = 6975, Deadly = 10350, Lethal = 20700

Supernova Pace (Red entries, math not shown)

Hard = 10400, Deadly = 15400, Lethal = 31050

Designer’s Note: Its important to remember that everything calculated up til now can be used for all encounters going forward. They only have to be changed when character’s level or magic items change.

Encounter 1

For the kickoff, DM Bob expects the party to conserve resources. They know the BBEG is in this cave, and will likely wait to unload. So he is assuming a Standard Adventure Pace for this encounter. The plan is to use a cabal of thunderwave wielding mages in a room filled with nasty pits that he can knock the party into.

Calculate Monster XP

He will use 12 CR 1 mages (200 xp each), which total = 2400 xp

Determine Party and Enemy Style

Enemy: Controller. The enemy’s focus on moving the party around into danger is a good example of a Controller style. Bob also considers Artillery with the large number of area effects, but ultimately the thunderwave damage is not very high, just a means to an end to get the party in the pits, so controller it will be.

Party: Melee. The DM knows that with his party conserving resources, they generally use their hard hitting frontliners to bring it home, and will consider it a Melee style.

Adjust XP for Encounter Modifier

With a focus on pit traps filled with damaging objects, DM Bob decides this is a Lethal Terrain type encounter.

Checking the chart: His party (melee) gets a +0 modifier for Lethal Terrain. However, the enemy controllers get a solid +2.

The overall encounter modifier = 2 – 0 = 2. This is a modifier of x1.2

Our new monster XP = 2000 x 1.2 = 2880 xp.

Adjust XP for Monster Number

For a 6 member party, 12 monsters is a x2.5 modifier.

Final XP = 2880 x 2.5 = 7200

7200 XP is a Deadly encounter for this party, which is right where DM Bob wants it. He wants the players to know that this is a big deal, and they have to stay on their toes. This is boss time, every fight could cost someone their lives!

Encounter 2

After a short rest and moving deeper into the icy complex, we have the big finale! DM Bob fully expects his party to go full out once they see their enemy, the evil White Dragon Killraxes!

Bob wants this to be a hell of a fight, but he is worried that an Adult White Dragon (even by itself) will just be too much for his roughly 5th level party. He decides to check the numbers to see if he’s in the ballpark.

Calculate Monster XP

CR 13 = 10,000 xp

Determine Party and Enemy Style

Enemy: Artillery. Killraxes is a blaster, preferring to fly around his cave and come in for big breath weapons…. An artillery style.

Party: Artillery. When the cleric and wizard go full out, they tend to like heavy fireballing…so DM Bob expects his party to adopt a more Artillery style in this fight.

Adjusted XP for Encounter Modifier

As just a baseline, DM bob decides to not to apply any special terrain yet, so we are at x1.0

XP = 10,000 x1.0 = 10,000

Adjusted XP for Monster Number

A single monster has trouble against a large 6 member party, and gets a x.5 modifier normally. However, Artillery get a bonus x.5, as more party members means more in the area of a breath weapon!

10,000 x1 = 10,000 xp.

Looking at a Supernova pace, DM Bob realizes that is not even a hard encounter for this party when they go full out. Though DM Bob knows the Dragon has a high CR and is more deadly than normal, he is emboldened, and decides to add a little more oomph.

Encounter 2 Take 2

DM Bob decides to add an icy floor that will crack and trip up the players, one that Killraxes will be immune to. He also thinks….maybe Killraxes has an apprentice, a young white dragon that has started to learn Killraxes’s ways. Lets see how this increases the difficulty of the encounter.

Calculate Monster XP

CR 13 + CR6 = 10,000 + 2300 = 12,300

Determine Party and Enemy Style

Enemy: Artillery. Party: Artillery.

Adjusted XP for Encounter Modifier

The ice conditions create a Difficult Terrain type encounter.

As Artillery, the enemy gets a +2 modifier. Normally the party as Artillery would too, but since the enemy is immune to the ice, they don’t get the bonus.

Encounter Modifier: 2 + 0 = 2. XP Modifier: x1.2

XP = 12,300 x1.2 = 14,760

Adjusted XP for Monster Number

Two monsters against a 6 player party is a x.75 modifier. As artillery, its another x.5 on top.

14760 x 1.25 = 18,450

At the Supernova pace, this is a nice solid Deadly range. Combining this with the high Cr of the dragon, Bob thinks this is probably a Lethal fight even if the party goes all out. Its all on the line now, Killraxes vs the party… and only one is coming out alive!
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So while there is a lot here, you may quickly note that the majority of the system is the same as the core one. So what is really different?

Modifiers for Player Ability and Magic Items: Characters thresholds are now longer just character level, we now adjust for a 6th level character run by a casual player that wants to throw dice and not think a bit vs a 6th level character run by a tactical genius who spends uncomfortable amounts of time on optimization boards.

We also have incorporated the power of magic items to further adjust the level of a player.

Encounter Types and Party Style
This is the heart of the changes. We first acknowledge that while there 1000s of different parties.... there are some very common "styles" that a group of PCS or monsters often uses. This gives us some insight as to how penalizing various conditions might be.

We then combine that with the Encounter types table, allowing us to very quickly modify our encounter PC for a narrow chokepoint, or a room filled with deadly pits, or a kobold ambush.

More Attention on Party Size
Party size is so incredibly important to overall party power, and yet the table in the core book really just kind of handwaves it outside of the 3-5 range. We at least incorporate that more precisely in our tables. Further, we make some acknowledgement that a low number of players are HIGHLY vulnerable to control effects. Meanwhile large parties are more susceptible to area blasts than normal, and we factor that in.

Actually factors in Encounters per day!
Our XP thresholds factor in the speed by his different parties play. You can adjust encounters for a once per day kind of random encounter or a 6 encounter expedition in a dungeon, all from one set of rules.

More Factors, but not a lot more Complex
At the end of the day, the charts do most of the work for us. The Effective Character levels are calculated only when a party levels or gains magic items, and so is something the DM only does infrequently.

The DM only needs to decide what style of fighting his enemies will do, picks a few terrain modifiers....and just adjusts the XP. Its a single new chart and one more multiplier....which could be easily incorporated into an encounter builder tool.

And yet we factor in many things that are so common to dnd that the base encounter system ignores.
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He / Him
This is really cool and a whole lot of work on your part! At first I was overwhelmed by all the calculations, but I realized (and you reminded) that most of the math you do once, and adjust only when the party changes.

I look forward to watching this grow!


I applaud the effort and certainly looks like a great start.

Really like that once you calibrate to any given party - you don't have to again for that party (except for major loot increments etc.)

Will give it a good look over and see what I can think of after that!


One early test. I'm curious what this method would spit back after being fed the data from the OP of this thread (the one that inspired the OP of this one).

We can put a lot of the pieces together but may need @Ancalagon to provide greater detail.

Just a thought.


One early test. I'm curious what this method would spit back after being fed the data from the OP of this thread (the one that inspired the OP of this one).

We can put a lot of the pieces together but may need @Ancalagon to provide greater detail.

Just a thought.
Keep in mind, the numbers here are bad, crap, garbage, broken.

The goal should not be any comparisons to actual, at least not yet. The goal right now is to try the system, does it feel intuitive, do the terrain types make sense, does it incorproate the kind of knobs you would expect a system to do.

Aka does it feel right using it. Don't think about the actual results right now...because I guarrantee you they are wrong:) (and if there not, its because I got stupidly luck).

That said, lets try it out and just see how the process would go:

Party: (without knowledge of any magical gear or the players themselves, we will just assume no magic gear and standard rank).

ECLs: 7, 7, 7

Party Style: Artillery (based on the use of multiple fireballs).
Enemy Style: Melee (ideally hill giants want to shake it up in melee).

Encounter Type: Standard (from what we know neither side was surprise or anything special, they just met and had a fight).

OEM: +0 +0 = 0 (no special modifiers on either side). x1.0 xp

Monster Number Modifier: x2 (3 monsters vs 3 PCs).

Modified Encounter XP: 1800 (CR 5) x 3 = 5,400, x2 = 10800. If we assume a Nova pace, that's between Deadly and lethal (again clearly not correct, but that's how you would do the calculation).

One adjustment we could consider. With such a bad initiative, perhaps we consider the PCs to get an ambush in the encounter. What does that do?

Encounter Modifier: 0 -4 = -4 (artillery gets a massive boost in ambush scenarios). OEM modifier: x.6

Modified XP: 1800 x 3 * .60 = 3,240 xp. That's in the Easy to Medium area of a Nova pace.....so that seems reasonable.
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Keep in mind, the numbers here are bad, crap, garbage, broken.

The goal should not be any comparisons to actual, at least not yet. The goal right now is to try the system, does it feel intuitive, do the terrain types make sense, does it incorproate the kind of knobs you would expect a system to do.

Aka does it feel right using it. Don't think about the actual results right now...because I guarrantee you they are wrong:) (and if there not, its because I got stupidly luck)

Well sure, but at some point, the numbers need to be filled in/calibrated.

I suppose a better thing to say would be hopefully this system can handle the encounter in that OP - at least at some point.

To calibrate the system we need some more standard/obvious encounters to provide some kind of baseline #s. How to get those, and in sufficient # to mean anything, is a tough question.


Dusty Dragon
Our most recent fight raises a lot of questions about this:

First, we had allies (... that did nothing for 2 rounds, but whatever), 2 awakened trees. They got pulped fast (round 3 and 4) but they did buy us time! How does that factor in, especially given the disparity in power (level 7 PCs, CR2 allies). I have no idea how to incorporate that in our calculations.

Second, magical items are not always useful in every fight. Our paladin has a giantslayer greatsword... which is just a +1 sword vs remoraz. His wand of ice was 100% ineffective.


Our most recent fight raises a lot of questions about this:

First, we had allies (... that did nothing for 2 rounds, but whatever), 2 awakened trees. They got pulped fast (round 3 and 4) but they did buy us time! How does that factor in, especially given the disparity in power (level 7 PCs, CR2 allies). I have no idea how to incorporate that in our calculations.

Second, magical items are not always useful in every fight. Our paladin has a giantslayer greatsword... which is just a +1 sword vs remoraz. His wand of ice was 100% ineffective.
So I probably would treat the trees as a "big resource" that was consumed, so I don't know if I would really adjust the encounter for it. Or you could consider the party to be at a Nova instead of standard pace to showcase the extra resource above normal that was expended. I do think there is probably a place in the model for the buffs you mentioned (especially bless, my lord is that spell insanely powerful, it completely changes encounter math as far as I am concerned)

The magic items is ultimately a compromise. Your right that for best results, a DM should evaluate if a magic item will have any use in a given fight....but that leads to a lot of tedious recalculation. One of the things the current system does is allow a DM to do one set of calculations for their party and then just leave that alone, and continue to use that for every encounter. That creates a lot of streamlining and power, but at the cost of some accuracy.

Ultimately my goal for this model is not to have a "perfect system" that is super accurate. I am just trying to get a more narrow range, so that we see less of the "my party just blitzed a deadly x2 like it was nothing". My taking into account magic items, even if there power varies from battle to battle, we still get a better overall picture of how powerful the group is, and that may be enough.

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