FallenRX
Adventurer
5e's encounter building in infamously messy, with some fights being marked as "even" being remarkably easier, and some fights listed as "Hard" not feeling like it, this make it hard to challenge players, and makes 5e's encounter design feel messy. (Its why you should play Level Up! 5e because its better at dealing with this).
But i've actually found out why.
First lets go into the whole Daily XP Budget/Adventuring day, and what that means.
You see the XP budget, is actually how this game is balanced, you see XP isn't just an arbitrary number for progress, its actually an estimate of the "power level" of a monster, it is quite literally a estimate of how much damage a monster can do before going down, and the Daily XP Budget? Is actually an estimate of how much health/damage players can actually have in adventuring day. I went into this more in this post if you wanna read about it
So when you are making an encounter, and looking at the XP Budget, its actually just estimating how much damage a monster can do to their total collective HP/HD pool before croaking. Thats all its doing. There is one thing about this though, the total XP Budget, is also under the assumption that at least one per day, the party will short rest, and use most of their hit dice to regain all of their health, if they do not do this, their Daily XP Budget is halved, this is important. (The reason the game says two Short rest per day, is because they assume that when your at around half health you will short rest, so you will on, average do this twice.)
(Fun Fact: Casters total Health/Damage XP budget mostly comes from their spells, without them they are way behind the curve, everytime a caster casts a spell the total XP from it drops because they are losing their defensive option/damage option.)
Now that last bit is important, because half of the XP Budget, is actually how encounter balancing is done, The "Easy", "Medium", etc, encounter difficulties are just how much damage a monster can do to that half XP budget, aka how much damage they can do before they are forced to short rest.
Easy is about 10-15%, Medium is about 25-30%, Hard is about 40%-45%, and Deadly is about 60-70%.
You can go check yourselves, but this basically is also the expected amount of damage a monster can do to the party, in a single encounter, knowing this alone you can basically make encounters about as flexible as you want, just simply stay under 90% of half of the XP Budget.
This is also where the 6-8 adventuring day comes from, because this means you can only take 6-8 encounters before literally not having enough health/HD) to continue using medium-hard encounters. That is all the Adventuring day means, its just talking about this, no other resources.
WHERE IT BREAKS
Now this is all fine and sound, and it actually works really well, but there is one fundamental issue with encounter building, one that broke it.
In the DMG, there is guidance on how to deal with multiple monsters, it starts at a 1x modifier and goes up for the multitudes of monsters you add starting at one monster. This seems sound, but it has one fundamental error, that actually breaks the encounter building of the game.
It does not account for action economy, the game tells you to adjust the XP modifier of the monster for each additional monster added to the encounter, but...doesnt account for your party size, and how to adjust it the monster's XP if its outnumbered.
Action economy is king in 5e, because of bounded accuracy, higher level monsters cannot just stat stick their way to tanking everything, they can reasonably be affected/hit by a bigger party, the actual math of the multipliers in the DMG are actually straight up broken and nonsense. A monster is worth less XP in the budget, because since they are outnumbered and out-actioned, they will due to this, likely take significantly more damage before they can act, meaning they less likely chance of doing their average damage expectation in the encounter before dying. This means when outnumbered monsters XP Budget is lowered in the multiplier, The multipliers in the DMG do not go into this or account for this at all. And instead gives you a completely broken methodology that actually does not work, its all complete nonsense, it was a rush job. Action Economy matters for the monsters too, because even if they can do the damage in stats, if they are outnumbered the odds of them having enough turns to do so is lessened. (This does not apply to legendary monsters since legendary actions actually lets them match the action economy.)
This fundamentally breaks 5e's encounter building, this poor multiplier guidelines in the DMG leads to encounters being easier, because its giving actively bad guidance on how to account for monster action economy, Even accounting for an average party of 4, Monsters drop a whole tier of difficulty if accounted for, Medium becomes Easy, Hard becomes Medium.
This is a Critical error in guidance in the DMG's part. And Its why 5e's encounter balancing is broken
Also note that The games current damage expectations from each encounter also lend itself to being easier, because they turned their old Easy difficulty from the playtest to the current medium.
So an already easier-made game, due to this error, is even easier and makes encounter building less accurate. Luckily this is easy to fix
HOW TO FIX THIS.
The first method simply just accounts for your party size in the XP value of an encounter properly(the DMG has a method of doing so but it is just as broken as the rest of it since it only matters if you have a notably bigger party, but not account for the advantage of just a party of 4). And here is a simply flx made by 5e brewer u/badooga1 here credit to him, he figured this out years ago. And beat me too making a post about this, but i feel im going for a more detailed approach here.
Making encounter building far more accurate.
The other major issue is how the encounter guidelines for a "Medium" or Easy encounter have been toned back to make it far too easy to fit the difficulty name.
So a simple adjustment to get encounters that actually fit with the names.
Thats all I hope this helps, and you run funner games.
TL/DR: The DMG guidelines for dealing with action economy against monsters is actually broken and bad, and not properly accounted for making encounters actually a whole difficulty easier, and making encounter balancing way harder.
Just make the encounter XP multiplier is equal to 3 ÷ the number of characters in the party, if its only 1 or 2 monsters. If its has 3 or more monsters, make the multiplier is equal to the number of monsters ÷ the number of characters in the party. And calculating the XP in the end, you get the actual how much that monster is worth in terms of power, for encounter building.
But i've actually found out why.
First lets go into the whole Daily XP Budget/Adventuring day, and what that means.
You see the XP budget, is actually how this game is balanced, you see XP isn't just an arbitrary number for progress, its actually an estimate of the "power level" of a monster, it is quite literally a estimate of how much damage a monster can do before going down, and the Daily XP Budget? Is actually an estimate of how much health/damage players can actually have in adventuring day. I went into this more in this post if you wanna read about it
So when you are making an encounter, and looking at the XP Budget, its actually just estimating how much damage a monster can do to their total collective HP/HD pool before croaking. Thats all its doing. There is one thing about this though, the total XP Budget, is also under the assumption that at least one per day, the party will short rest, and use most of their hit dice to regain all of their health, if they do not do this, their Daily XP Budget is halved, this is important. (The reason the game says two Short rest per day, is because they assume that when your at around half health you will short rest, so you will on, average do this twice.)
(Fun Fact: Casters total Health/Damage XP budget mostly comes from their spells, without them they are way behind the curve, everytime a caster casts a spell the total XP from it drops because they are losing their defensive option/damage option.)
Now that last bit is important, because half of the XP Budget, is actually how encounter balancing is done, The "Easy", "Medium", etc, encounter difficulties are just how much damage a monster can do to that half XP budget, aka how much damage they can do before they are forced to short rest.
Easy is about 10-15%, Medium is about 25-30%, Hard is about 40%-45%, and Deadly is about 60-70%.
You can go check yourselves, but this basically is also the expected amount of damage a monster can do to the party, in a single encounter, knowing this alone you can basically make encounters about as flexible as you want, just simply stay under 90% of half of the XP Budget.
This is also where the 6-8 adventuring day comes from, because this means you can only take 6-8 encounters before literally not having enough health/HD) to continue using medium-hard encounters. That is all the Adventuring day means, its just talking about this, no other resources.
WHERE IT BREAKS
Now this is all fine and sound, and it actually works really well, but there is one fundamental issue with encounter building, one that broke it.
In the DMG, there is guidance on how to deal with multiple monsters, it starts at a 1x modifier and goes up for the multitudes of monsters you add starting at one monster. This seems sound, but it has one fundamental error, that actually breaks the encounter building of the game.
It does not account for action economy, the game tells you to adjust the XP modifier of the monster for each additional monster added to the encounter, but...doesnt account for your party size, and how to adjust it the monster's XP if its outnumbered.
Action economy is king in 5e, because of bounded accuracy, higher level monsters cannot just stat stick their way to tanking everything, they can reasonably be affected/hit by a bigger party, the actual math of the multipliers in the DMG are actually straight up broken and nonsense. A monster is worth less XP in the budget, because since they are outnumbered and out-actioned, they will due to this, likely take significantly more damage before they can act, meaning they less likely chance of doing their average damage expectation in the encounter before dying. This means when outnumbered monsters XP Budget is lowered in the multiplier, The multipliers in the DMG do not go into this or account for this at all. And instead gives you a completely broken methodology that actually does not work, its all complete nonsense, it was a rush job. Action Economy matters for the monsters too, because even if they can do the damage in stats, if they are outnumbered the odds of them having enough turns to do so is lessened. (This does not apply to legendary monsters since legendary actions actually lets them match the action economy.)
This fundamentally breaks 5e's encounter building, this poor multiplier guidelines in the DMG leads to encounters being easier, because its giving actively bad guidance on how to account for monster action economy, Even accounting for an average party of 4, Monsters drop a whole tier of difficulty if accounted for, Medium becomes Easy, Hard becomes Medium.
This is a Critical error in guidance in the DMG's part. And Its why 5e's encounter balancing is broken
Also note that The games current damage expectations from each encounter also lend itself to being easier, because they turned their old Easy difficulty from the playtest to the current medium.
So an already easier-made game, due to this error, is even easier and makes encounter building less accurate. Luckily this is easy to fix
HOW TO FIX THIS.
The first method simply just accounts for your party size in the XP value of an encounter properly(the DMG has a method of doing so but it is just as broken as the rest of it since it only matters if you have a notably bigger party, but not account for the advantage of just a party of 4). And here is a simply flx made by 5e brewer u/badooga1 here credit to him, he figured this out years ago. And beat me too making a post about this, but i feel im going for a more detailed approach here.
This basically adjusts the issues and gives you more balanced encounters in general that actually account for the action economy in total when building them.The total XP multiplier is equal to the number of monsters (or 3, whichever is higher) ÷ the number of characters in the party.
(The minimum of 3 is meant to represent boss fights that have legendary and possibly mythic actions. Furthermore, contributions from very weak monsters to this calculation can be excluded or reduced as appropriate.)
Making encounter building far more accurate.
The other major issue is how the encounter guidelines for a "Medium" or Easy encounter have been toned back to make it far too easy to fit the difficulty name.
So a simple adjustment to get encounters that actually fit with the names.
This will get you more challenging and accurate to name encounters in the system, and allow you to flexibly build encounters easily.Halve the daily xp budget.
And just add monsters while trying to stay under 90% that. That is the absolute maximum they can take before they will certainly die without extra resources.
25% of it is easy, 50% of it is medium., 75% of it is Tough. 80-90% is Deadly.
Try to avoid 100% or over, without some serious resources to mitigate this, your party would. certainly, die.They can only handle 100% before needing to short rest, and 200% total daily.
Thats all I hope this helps, and you run funner games.
TL/DR: The DMG guidelines for dealing with action economy against monsters is actually broken and bad, and not properly accounted for making encounters actually a whole difficulty easier, and making encounter balancing way harder.
Just make the encounter XP multiplier is equal to 3 ÷ the number of characters in the party, if its only 1 or 2 monsters. If its has 3 or more monsters, make the multiplier is equal to the number of monsters ÷ the number of characters in the party. And calculating the XP in the end, you get the actual how much that monster is worth in terms of power, for encounter building.