Korahir
2017-06-09, 09:11 AM
Hello fellow playgrounders,
quite regularly threads like "Is this a good boss fight for my PCs?" or "TPK - what happened?" pop up in this subforum. Because of this I thought I write a mini guide for DMs that should help them create encounters.
Why not rely on CR?
CR is a simplification for a very complex thing. It is a good starting point. A Balor is not an appropriate encounter for a group of 4 level 3 PCs. A Balor could be a a challenge for a group of 4 level 20 PCs but most likely 4 level 20 PCs mop the floor with a single Balor. This guide should help you identify why.
Addendum: As Zanos pointed out, an important rule is that your party is supposed to encounter an encounter with CR equal to the APL (average party level) four times per day. If your party has only a single fight each day, CR should be at least +2 of the APL (depending on party composition this may be even higher).
First step: Know your party! In detail!
Yeah I know we all been to the one shots or games with unknown players but usually DMs know the party composition and all the details of the PCs beforehand.
I recommend having a spreadsheet where you gather the most important data of your PCs. The amount of data you need surely isn't nearly as much as you think. I have used a rather excessive spreadsheet that includes average, lowest and highest values in many important stats: HP, AC, saves, Attack bonus (melee and ranged), average damage per attack(melee and ranged), max damage per round (melee and ranged), etc before. I also gather the DCs for the offensive power of my party: save or sucks(die), short time disables (stuns, paralyze, nauseated etc.) and debuffs(shaken, sickened, poisoned, etc.). Other very important details to know is modes of movement: can the party fly, if so how many can. Can they swim, burrow? Whats their fastest land speed. Lastly know their senses: Darkvision, low light vision, true sight, blindsense, mindsight and the likes.
You should be able to answer the following questions about your party:
Who has the lowest HP in the party?
Who has the lowest AC in the party?
Who has the lowest saves?
Do my PCs differ substantially in these defensive aspects (you need this for AoE effects).
What's the attack routine of each of them?
Do they rely on melee or ranged attacks?
Do they rely on spells?
What offensive spells do they use?
What defensive spells do they use?
What are their possible modes of movement?
What senses do they have?
Second step: Know the monster(s)
Pretty much the same as with the party: know the strengths and weaknesses of the monster(s) you want to use. You can focus on the same question I wrote about your party. Then compare the offensive and defensive potential of the monster with your party stats. If you send your dedicated fire orb throwing evoker a horde of plants, he will rejoice and end the fight before you did set it up.
Third step: Know the environment
The environment of an encounter is key to its outcome. Especially vision, senses and modes of movement are relevant. Underwater fights are a nightmare for groups who aren't specialized in it. Flying monsters with ranged attacks invalidate all melee PCs that aren't able to fly. PCs with no way of illuminating a cave will probably die to a single monster with darkvision if they cannot outrun it. So ask yourself the following:
Does the environment require a special sense for anyone to fight in it effectively?
Does the environment require a certain mode of movement to fight in it effectively?
Does the environment influence a certain form of attack (i.e. wind vs ranged attacks, underwater vs. spells with the fire descriptor etc.)?
Fourth step: Who is prepared for the fight?
One of the most underestimated part of a fight is preparation. Fighting plants with a fire spell prepared is a hell lot easier than running into them without any chance of dealing fire damage. PCs often gather information before entering a battle: this knowledge is key in encounter design. Imagine a cleric knowing he will fight a demon. Usually demons are hard to lock down because of ther teleport abilities. Now said cleric knew what he would encounter and has dimensional anchor prepared. All of a sudden a major strength of the monster has been taken away. Question to ask yourself:
Who is prepared for the fight?
Which strengths are circumvented by the preparation of one of the combatants?
Which weaknesses are targeted because of better preparation?
Will the party or the monster be surprised by the attack?
Fifth step: The fight
Now let's take all our answers and answer some more questions with them. These are the most important questions to know whether or not your encounter is worth its CR.
Who will win initiative? Is a oneshot likely?
Initiative and/or surprise rounds can turn around many fights. If you go first, you hit first, you deal damage first. Sometimes DnD in high levels is referred to playing rocket tag. The meaning behind this is that especially dedicated damage dealers are built in a way to deal enough damage on average to kill every monster at their CR that has average HP and AC. This is why step 1 and 2 are so crucial: no matter if the PCs ptoentially one hit the monster or the other way round, be wary when running such an encounter. Ideally the side that can one shot the opponent doesn't win initiative.
You may know this design from low level encounters: spring a trap with lower CR creatures and win initiative thereby increasing the difficulty of the encounter. Linked to the question is also the question if anyone relies on enemies being flatfooted for additional damage. A surprise attack by rogue like monsters is way more dangerous than an attack by roguelike monsterss when the party is aware of them.
Linked to winning initiative is the use of save or suck: Some caster specialize in going first and ending the encounter before it started.
Who will win the action economy?
The second most important part about fighting is action economy. Inexperienced DMs ofter wonder why a single big bad evil guy wasn't able to do anything to the PCs. Well, it is simple: if your party consists of 4 players and you use only 1 monster your party has four times the actions of the monster. Action economy is something players often try to break by spell usage (i.e. celertiy, time stop, polymorph, summon spells etc.). Cohorts, animal companions and familiars are powerful because they add actions to the party. I recommend to always use encounters with multiple monsters so that your players don't win the action economy by default.
Can every monster and player contribute to the fight?
This is soooo important. Ever sat down at a table to watch a fight you couldn't participate? Famous examples can be read everywhere. I think the most recent one I read in the forums was a monk in a ship fight that ducked away behind cover for 10(?) rounds. That is horrible game mastering but the same should apply to monsters: don't include a monster in the fight that cannot contribute: a non flying monster in an aerial flight is pointless.
Showcase the strengths of the PCs and the monster(s)
Now this is often a little hard to do but keep in mind: you want the PCs to be able to showcase their "special moves". Give them a chance to do so. My gaming group still talks about the time a single confusion spell wiped out a hill giant raiding party.
Sixth step: do not repeat yourself
Ever fought three goblin hordes in a row? Orc Barbarian raiding party at every crossroads? The Wyvern mountains with nothing but wyvern? Try not to repeat yourself in your encounter patterns. If you threw an encounter featuring undead at the PCs to let the cleric shine maybe follow it up by an elven war criminal and his friends to hunt down for the ranger who happens to have elves as favored enemies. Change environment, change encounter set ups, include traps in monster encounters, have social situations become tense.
quite regularly threads like "Is this a good boss fight for my PCs?" or "TPK - what happened?" pop up in this subforum. Because of this I thought I write a mini guide for DMs that should help them create encounters.
Why not rely on CR?
CR is a simplification for a very complex thing. It is a good starting point. A Balor is not an appropriate encounter for a group of 4 level 3 PCs. A Balor could be a a challenge for a group of 4 level 20 PCs but most likely 4 level 20 PCs mop the floor with a single Balor. This guide should help you identify why.
Addendum: As Zanos pointed out, an important rule is that your party is supposed to encounter an encounter with CR equal to the APL (average party level) four times per day. If your party has only a single fight each day, CR should be at least +2 of the APL (depending on party composition this may be even higher).
First step: Know your party! In detail!
Yeah I know we all been to the one shots or games with unknown players but usually DMs know the party composition and all the details of the PCs beforehand.
I recommend having a spreadsheet where you gather the most important data of your PCs. The amount of data you need surely isn't nearly as much as you think. I have used a rather excessive spreadsheet that includes average, lowest and highest values in many important stats: HP, AC, saves, Attack bonus (melee and ranged), average damage per attack(melee and ranged), max damage per round (melee and ranged), etc before. I also gather the DCs for the offensive power of my party: save or sucks(die), short time disables (stuns, paralyze, nauseated etc.) and debuffs(shaken, sickened, poisoned, etc.). Other very important details to know is modes of movement: can the party fly, if so how many can. Can they swim, burrow? Whats their fastest land speed. Lastly know their senses: Darkvision, low light vision, true sight, blindsense, mindsight and the likes.
You should be able to answer the following questions about your party:
Who has the lowest HP in the party?
Who has the lowest AC in the party?
Who has the lowest saves?
Do my PCs differ substantially in these defensive aspects (you need this for AoE effects).
What's the attack routine of each of them?
Do they rely on melee or ranged attacks?
Do they rely on spells?
What offensive spells do they use?
What defensive spells do they use?
What are their possible modes of movement?
What senses do they have?
Second step: Know the monster(s)
Pretty much the same as with the party: know the strengths and weaknesses of the monster(s) you want to use. You can focus on the same question I wrote about your party. Then compare the offensive and defensive potential of the monster with your party stats. If you send your dedicated fire orb throwing evoker a horde of plants, he will rejoice and end the fight before you did set it up.
Third step: Know the environment
The environment of an encounter is key to its outcome. Especially vision, senses and modes of movement are relevant. Underwater fights are a nightmare for groups who aren't specialized in it. Flying monsters with ranged attacks invalidate all melee PCs that aren't able to fly. PCs with no way of illuminating a cave will probably die to a single monster with darkvision if they cannot outrun it. So ask yourself the following:
Does the environment require a special sense for anyone to fight in it effectively?
Does the environment require a certain mode of movement to fight in it effectively?
Does the environment influence a certain form of attack (i.e. wind vs ranged attacks, underwater vs. spells with the fire descriptor etc.)?
Fourth step: Who is prepared for the fight?
One of the most underestimated part of a fight is preparation. Fighting plants with a fire spell prepared is a hell lot easier than running into them without any chance of dealing fire damage. PCs often gather information before entering a battle: this knowledge is key in encounter design. Imagine a cleric knowing he will fight a demon. Usually demons are hard to lock down because of ther teleport abilities. Now said cleric knew what he would encounter and has dimensional anchor prepared. All of a sudden a major strength of the monster has been taken away. Question to ask yourself:
Who is prepared for the fight?
Which strengths are circumvented by the preparation of one of the combatants?
Which weaknesses are targeted because of better preparation?
Will the party or the monster be surprised by the attack?
Fifth step: The fight
Now let's take all our answers and answer some more questions with them. These are the most important questions to know whether or not your encounter is worth its CR.
Who will win initiative? Is a oneshot likely?
Initiative and/or surprise rounds can turn around many fights. If you go first, you hit first, you deal damage first. Sometimes DnD in high levels is referred to playing rocket tag. The meaning behind this is that especially dedicated damage dealers are built in a way to deal enough damage on average to kill every monster at their CR that has average HP and AC. This is why step 1 and 2 are so crucial: no matter if the PCs ptoentially one hit the monster or the other way round, be wary when running such an encounter. Ideally the side that can one shot the opponent doesn't win initiative.
You may know this design from low level encounters: spring a trap with lower CR creatures and win initiative thereby increasing the difficulty of the encounter. Linked to the question is also the question if anyone relies on enemies being flatfooted for additional damage. A surprise attack by rogue like monsters is way more dangerous than an attack by roguelike monsterss when the party is aware of them.
Linked to winning initiative is the use of save or suck: Some caster specialize in going first and ending the encounter before it started.
Who will win the action economy?
The second most important part about fighting is action economy. Inexperienced DMs ofter wonder why a single big bad evil guy wasn't able to do anything to the PCs. Well, it is simple: if your party consists of 4 players and you use only 1 monster your party has four times the actions of the monster. Action economy is something players often try to break by spell usage (i.e. celertiy, time stop, polymorph, summon spells etc.). Cohorts, animal companions and familiars are powerful because they add actions to the party. I recommend to always use encounters with multiple monsters so that your players don't win the action economy by default.
Can every monster and player contribute to the fight?
This is soooo important. Ever sat down at a table to watch a fight you couldn't participate? Famous examples can be read everywhere. I think the most recent one I read in the forums was a monk in a ship fight that ducked away behind cover for 10(?) rounds. That is horrible game mastering but the same should apply to monsters: don't include a monster in the fight that cannot contribute: a non flying monster in an aerial flight is pointless.
Showcase the strengths of the PCs and the monster(s)
Now this is often a little hard to do but keep in mind: you want the PCs to be able to showcase their "special moves". Give them a chance to do so. My gaming group still talks about the time a single confusion spell wiped out a hill giant raiding party.
Sixth step: do not repeat yourself
Ever fought three goblin hordes in a row? Orc Barbarian raiding party at every crossroads? The Wyvern mountains with nothing but wyvern? Try not to repeat yourself in your encounter patterns. If you threw an encounter featuring undead at the PCs to let the cleric shine maybe follow it up by an elven war criminal and his friends to hunt down for the ranger who happens to have elves as favored enemies. Change environment, change encounter set ups, include traps in monster encounters, have social situations become tense.