House Rule: Knowing Something About Monsters [Archive] - Wizards Community

House Rule: Knowing Something About Monsters [Archive] - Wizards Community

Post/Author/DateTime Post
Nerdkid7
05-25-07, 04:47 PM I'm soon going to start a campaign (First time DMing), and I was wondering if a certain house rule I created is balanced/fair.

I've played with the PCs before, and I know they tend to look at the monster manual to see what tactics to use against monsters in encounters. I know this is totally unfair (unfair to the DM, anyway). Moreover, who, as a PC, wouldn't be interested in looking at monsters when a game is not in session? Checking the stats of interesting monsters.

When encountering these monsters that they've researched (out-of-character), I think they shouldn't use that knowledge when fighting the monster. I mean it's true, there's no avoiding it (If they know that a monster has a weakness under certain conditions but they also know their character might not know that weakness, I doubt they would ignore the weakness altogether).

So I was thinking of a house rule that doesn't necessarily prevent them from knowing ANYTHING about a monster, but at the same time, may limit what they do know. I'm going to create an Adventurer's Guild that passes out periodicals on monsters (mostly common monsters).

The house rule is, as long as they subscribe to the periodicals (and read them when they come out--monthly), they can roll an intelligent check vs the monster's HD (PC 1d20 + Int Mod VS DM 1d20 + Monster HD). SUCCESS means that they know a little bit about the monster's tactics (Perhaps a natural 20 could even know slightly more--like a detailed way of taking care of the monster). FAILURE means that dont know anything extra (They may know something about the monster from previous battles, but can't remember if there were any articles on the monster). Failure also means that they cannot make that roll again against the same monster until next month (when they get another periodical).

I think this would make the players be willing to roll to see if they know anything about the monster, and discourage them from using outside knowledge (since we would be discussing what they DO know from this check).

I was also thinking this could apply to a Ranger's Favored Enemy Class Feature--but I wasn't sure how to limit it (the periodicals on monsters comes out monthly, so failure means they can't roll against the same monster until next month). Perhaps for Favored Enemy, the ranger can roll once against the certain monster (of course, of a type that is one of his favored enemies) in his/her whole lifetime; success means he/she knows a little bit; failure means he/she knows nothing (but of course still gets the bluff, listen, spot, etc bonuses from Favored Enemy). This roll can be done for any monster, as long as the monster has not been rolled on before and is under one of his/her chosen favored enemies.

What do you think? Is this balanced/fair? I think, as PCs level up and encounter higher leveled monsters, it becomes harder and harder to know (and therefore roll for) anything about monsters (as monster's HD increases). I wanted it to apply mostly to low level encounters anyway (one of the PCs is actually being newly introduced into D&D).

Hit me up with your opinions! :blink:
Morwen
05-25-07, 05:14 PM Such a system is already in place in D&D. They're called Knowledge skill checks. For instance, Knowledge (arcana) checks can give you information about Dragons, Magical Beasts, and Constructs, while Knowledge (religion) checks can give you information about Undeads. The Knowledge skill description describes which knowledge skills are relevant for each monster type.

The DC of the check is generally equal to 10 + the monster's HD.
Seldriss
05-26-07, 10:07 AM You can also use Knowledge/Monsters.
But the DC is 20 plus the monster CR.
Tequila_Sunrise
05-27-07, 02:20 PM Your knowledge DCs will be too high even for a wizard to make most of the time. If your players are really into metagaming, it's easy to use that to your advantage: describe/play your monsters differently or just make new monsters.

In my latest session as DM, my players had to fight a purple polka dotted dragon. I kid you not. Anyway, one player rolled a high Knowledge (arcana) check, so I told her what I wanted the players to know about the dragon and no more.
Ra-Tiel
05-27-07, 02:52 PM [...] The DC of the check is generally equal to 10 + the monster's HD.
And this is already the current system's weak point. It does not take into account common knowledge about a family or larger group of monsters, nor does it acknowledge previously known information or extra research.

Under the current system, it was (by the rules) perfectly legal for a character to...

... know that a wyrmling red dragon is immune to fire, but having no idea that the great red wyrm is also immune to fire.
... one day know that you must use acid or fire on a hydra's heads to prevent them from regrowing, but having no idea about it the next day.
... be in a library full with records and books, and scrolls, and stuff, but not being able to gain more information than if he was woken up in the middle of the night and pressed for an anwser at knife-point.
Seldriss
05-27-07, 06:20 PM I also think that a DC10+HD would be too easy.
Of course, DC20+CR is pretty high and difficult to reach. But that's also the point. The information given in case of success is important and can help to beat the monster, taking advantage from its vulnerabilities. So it has to be difficult to get.
Note also that i said CR, not HD.
Holy_Beholder
05-27-07, 07:06 PM I would think that the players would get to take notes. If for instance you made the Knowledge check against a hydra, you get to note that a hydra is weak to fire and acid, and can use that later. You don't get to know about other headed hydras, but it would be okay to guess(well, the 5 headed hydra and the 8 headed hydra could lose regeneration of their heads to fire and acid, so this 11 headed hydra probably will too) Its the same thing with dragons and colors(well the little guy wouldn't burn and breathed fire, so this one probably won't either) This is really useful when you have lots of new monsters, I have used it, and it made sense. For instance, a weaker type of dragon, called a Drake(no spells, but better spell resistance) could be guessed easily. However, it came as a surprise when it was also capable of breathing long range fireballs, but the party did have an idea about fire and spell resistance.
Ra-Tiel
05-28-07, 03:41 AM I would think that the players would get to take notes. If for instance you made the Knowledge check against a hydra, you get to note that a hydra is weak to fire and acid, and can use that later. You don't get to know about other headed hydras, but it would be okay to guess(well, the 5 headed hydra and the 8 headed hydra could lose regeneration of their heads to fire and acid, so this 11 headed hydra probably will too) Its the same thing with dragons and colors(well the little guy wouldn't burn and breathed fire, so this one probably won't either) This is really useful when you have lots of new monsters, I have used it, and it made sense. For instance, a weaker type of dragon, called a Drake(no spells, but better spell resistance) could be guessed easily. However, it came as a surprise when it was also capable of breathing long range fireballs, but the party did have an idea about fire and spell resistance.
True. However, RAW it's as I described it above. The various Knowledge skills represent your character's knowledge about certain topics, and in no way mentiones that you get to keep notes, or retain previous knowledge. Although I also think that'd be called "common sense" (and if I DMed I would make that a house rule), it is not included in the rules.

The point is, by the rules, if you make that K(arcana) check against DC 17, you know that the red wyrmling is immune to fire. But, if you fail the K(arcana) check against DC 50, you know nothing about the great red wyrm. And that's the silly thing.

Also, I think folding "monster lore" into the normal Knowledge skills was a big mistake. Although the designers' goal was to make all Knowledge skills somewhat useful, it doesn't make any sense that way. Why should K(local), which represents knowledge about regional customs and events, allow me to know that a troll's regeneration is circumvented by fire damage, or what spell-like abilities a storm giant has? :uh-huh:

Imho a type-based Knowledge skill "monster lore" or such would be best. This way you can seperate the "adventuring info" from the "common info", and become a bit more creative with the DCs without making the skill too powerful. For example, in my own setting I handle it like this:

[...]

Identifying a specific monster or creature type requires a successful skill check (with the appropriate type in Monster Lore). The TN depends on what you try to find out about the creature. Knowing its ability values has TN 5 + its level. Knowing its skill modifiers has TN 10 + its level. Knowing its feats has TN 15 + its level. Knowing its magical abilities (if any) has TN 20 + its level. Thus you can make up to four checks for each creature, to see what you know about its abilities, skills, feats, and magical powers. Once you know a fact about a monster, you should write it down on a note sheet to prevent your character from "mysteriously forgetting" information he had known just a few days ago.

[...]

I seperated what you can know about a monster. Knowing a monster's ability scores is probably the easiest, with skills and feats following, and last (and most difficult to discern) are any magical abilities.

It may not be perfect, and may require some more tinkering, but I think it's a good step in the right direction.
Arcade
05-28-07, 09:26 AM there was an article on the D&D page not too long ago about knowing about common monsters. For instance, trolls are common enough in stories and more common than their 5 Hd indicate. For cases like this, you can adjust the DC appropriately.

For the dragons, you could see how well their DC does against a dragon of any age category. So if they pass the DC against a wyrmling, they can know that all red dragons are immune to fire, vulnerable to cold and breathe fire. But they have no knowledge of spell like abilities for older dragons or how large the breath weapons can get or that dragons cast spells. They'd need to pass the DC for higher age categories to learn that.

The general idea behind DC of 10+HD is as a measure or rarity in the campaign world. High hit die creatures are generally more rare than low HD ones, but it's not necessarily true so you can adjust it.

And for being in a library, you can definitely give the rolls a +2 bonus, and possibly even extra rolls if they spend multiple days in the library. hiring researches can give aid another bonuses. Also, my players consult sages who have good knowledge checks and libraries to find out this stuff.
Ecalsneerg
05-28-07, 10:10 AM I was also thinking this could apply to a Ranger's Favored Enemy Class Feature--but I wasn't sure how to limit it (the periodicals on monsters comes out monthly, so failure means they can't roll against the same monster until next month). Perhaps for Favored Enemy, the ranger can roll once against the certain monster (of course, of a type that is one of his favored enemies) in his/her whole lifetime; success means he/she knows a little bit; failure means he/she knows nothing (but of course still gets the bluff, listen, spot, etc bonuses from Favored Enemy). This roll can be done for any monster, as long as the monster has not been rolled on before and is under one of his/her chosen favored enemies.
Why would a Ranger get bonuses for Favored Enemy if he knew nothing about the monster? I've always assumed Favored Enemy gave you a working level knowledge of a monster. Personally, I advocate it giving bonuses to Knowledge checks relating the enemy in question, and giving, say a DC 5 or 10 level of knowledge on their favored enemies.
Kradlo
05-28-07, 10:47 AM You can also use Knowledge/Monsters.
But the DC is 20 plus the monster CR.

There is no Knowledge (Monsters) skill. The Knowledge skills for identifying monsters is detailed in the PHB.

In my campaign, I make adjustments to the DC based on commonality of the creature and other circumstances. A ranger that has Magical Beasts as his favored enemy gains a circumstance bonus on Knowledge (Arcana) checks to identify magical beasts equal to his favored enemy bonus.

If trolls are a common threat in an area, the DC to identify them may be 5 lower, or even 10 lower, depending on how common they are.

"Trolls? Yeah, they attack every winter, so we keep barrels of oil stacked by the city walls, and plenty of torches. That, and the king's wizard is right handy with fire spells."

The GM is judge of what is and what is not common knowledge for his campaign.
Krusk
05-28-07, 11:59 AM We use 10+HD, but if the enemy has less than 3 or 4 HD no roll is needed. Anyone can just know it. In the case of dragons where they would know younger forms are immune to fire, but know nothing about the older forms. I usually read the info i would give for the oldest form they would know about, and then tell them something like "but this one looks much bigger/older" so they get a general idea. Never had a problem with this system.

Post/Author/DateTime	Post
Nerdkid7 05-25-07, 04:47 PM	I'm soon going to start a campaign (First time DMing), and I was wondering if a certain house rule I created is balanced/fair. I've played with the PCs before, and I know they tend to look at the monster manual to see what tactics to use against monsters in encounters. I know this is totally unfair (unfair to the DM, anyway). Moreover, who, as a PC, wouldn't be interested in looking at monsters when a game is not in session? Checking the stats of interesting monsters. When encountering these monsters that they've researched (out-of-character), I think they shouldn't use that knowledge when fighting the monster. I mean it's true, there's no avoiding it (If they know that a monster has a weakness under certain conditions but they also know their character might not know that weakness, I doubt they would ignore the weakness altogether). So I was thinking of a house rule that doesn't necessarily prevent them from knowing ANYTHING about a monster, but at the same time, may limit what they do know. I'm going to create an Adventurer's Guild that passes out periodicals on monsters (mostly common monsters). The house rule is, as long as they subscribe to the periodicals (and read them when they come out--monthly), they can roll an intelligent check vs the monster's HD (PC 1d20 + Int Mod VS DM 1d20 + Monster HD). SUCCESS means that they know a little bit about the monster's tactics (Perhaps a natural 20 could even know slightly more--like a detailed way of taking care of the monster). FAILURE means that dont know anything extra (They may know something about the monster from previous battles, but can't remember if there were any articles on the monster). Failure also means that they cannot make that roll again against the same monster until next month (when they get another periodical). I think this would make the players be willing to roll to see if they know anything about the monster, and discourage them from using outside knowledge (since we would be discussing what they DO know from this check). I was also thinking this could apply to a Ranger's Favored Enemy Class Feature--but I wasn't sure how to limit it (the periodicals on monsters comes out monthly, so failure means they can't roll against the same monster until next month). Perhaps for Favored Enemy, the ranger can roll once against the certain monster (of course, of a type that is one of his favored enemies) in his/her whole lifetime; success means he/she knows a little bit; failure means he/she knows nothing (but of course still gets the bluff, listen, spot, etc bonuses from Favored Enemy). This roll can be done for any monster, as long as the monster has not been rolled on before and is under one of his/her chosen favored enemies. What do you think? Is this balanced/fair? I think, as PCs level up and encounter higher leveled monsters, it becomes harder and harder to know (and therefore roll for) anything about monsters (as monster's HD increases). I wanted it to apply mostly to low level encounters anyway (one of the PCs is actually being newly introduced into D&D). Hit me up with your opinions! :blink:
Morwen 05-25-07, 05:14 PM	Such a system is already in place in D&D. They're called Knowledge skill checks. For instance, Knowledge (arcana) checks can give you information about Dragons, Magical Beasts, and Constructs, while Knowledge (religion) checks can give you information about Undeads. The Knowledge skill description describes which knowledge skills are relevant for each monster type. The DC of the check is generally equal to 10 + the monster's HD.
Seldriss 05-26-07, 10:07 AM	You can also use Knowledge/Monsters. But the DC is 20 plus the monster CR.
Tequila_Sunrise 05-27-07, 02:20 PM	Your knowledge DCs will be too high even for a wizard to make most of the time. If your players are really into metagaming, it's easy to use that to your advantage: describe/play your monsters differently or just make new monsters. In my latest session as DM, my players had to fight a purple polka dotted dragon. I kid you not. Anyway, one player rolled a high Knowledge (arcana) check, so I told her what I wanted the players to know about the dragon and no more.
Ra-Tiel 05-27-07, 02:52 PM	[...] The DC of the check is generally equal to 10 + the monster's HD. And this is already the current system's weak point. It does not take into account common knowledge about a family or larger group of monsters, nor does it acknowledge previously known information or extra research. Under the current system, it was (by the rules) perfectly legal for a character to... ... know that a wyrmling red dragon is immune to fire, but having no idea that the great red wyrm is also immune to fire. ... one day know that you must use acid or fire on a hydra's heads to prevent them from regrowing, but having no idea about it the next day. ... be in a library full with records and books, and scrolls, and stuff, but not being able to gain more information than if he was woken up in the middle of the night and pressed for an anwser at knife-point.
Seldriss 05-27-07, 06:20 PM	I also think that a DC10+HD would be too easy. Of course, DC20+CR is pretty high and difficult to reach. But that's also the point. The information given in case of success is important and can help to beat the monster, taking advantage from its vulnerabilities. So it has to be difficult to get. Note also that i said CR, not HD.
Holy_Beholder 05-27-07, 07:06 PM	I would think that the players would get to take notes. If for instance you made the Knowledge check against a hydra, you get to note that a hydra is weak to fire and acid, and can use that later. You don't get to know about other headed hydras, but it would be okay to guess(well, the 5 headed hydra and the 8 headed hydra could lose regeneration of their heads to fire and acid, so this 11 headed hydra probably will too) Its the same thing with dragons and colors(well the little guy wouldn't burn and breathed fire, so this one probably won't either) This is really useful when you have lots of new monsters, I have used it, and it made sense. For instance, a weaker type of dragon, called a Drake(no spells, but better spell resistance) could be guessed easily. However, it came as a surprise when it was also capable of breathing long range fireballs, but the party did have an idea about fire and spell resistance.
Ra-Tiel 05-28-07, 03:41 AM	I would think that the players would get to take notes. If for instance you made the Knowledge check against a hydra, you get to note that a hydra is weak to fire and acid, and can use that later. You don't get to know about other headed hydras, but it would be okay to guess(well, the 5 headed hydra and the 8 headed hydra could lose regeneration of their heads to fire and acid, so this 11 headed hydra probably will too) Its the same thing with dragons and colors(well the little guy wouldn't burn and breathed fire, so this one probably won't either) This is really useful when you have lots of new monsters, I have used it, and it made sense. For instance, a weaker type of dragon, called a Drake(no spells, but better spell resistance) could be guessed easily. However, it came as a surprise when it was also capable of breathing long range fireballs, but the party did have an idea about fire and spell resistance. True. However, RAW it's as I described it above. The various Knowledge skills represent your character's knowledge about certain topics, and in no way mentiones that you get to keep notes, or retain previous knowledge. Although I also think that'd be called "common sense" (and if I DMed I would make that a house rule), it is not included in the rules. The point is, by the rules, if you make that K(arcana) check against DC 17, you know that the red wyrmling is immune to fire. But, if you fail the K(arcana) check against DC 50, you know nothing about the great red wyrm. And that's the silly thing. Also, I think folding "monster lore" into the normal Knowledge skills was a big mistake. Although the designers' goal was to make all Knowledge skills somewhat useful, it doesn't make any sense that way. Why should K(local), which represents knowledge about regional customs and events, allow me to know that a troll's regeneration is circumvented by fire damage, or what spell-like abilities a storm giant has? :uh-huh: Imho a type-based Knowledge skill "monster lore" or such would be best. This way you can seperate the "adventuring info" from the "common info", and become a bit more creative with the DCs without making the skill too powerful. For example, in my own setting I handle it like this: [...] Identifying a specific monster or creature type requires a successful skill check (with the appropriate type in Monster Lore). The TN depends on what you try to find out about the creature. Knowing its ability values has TN 5 + its level. Knowing its skill modifiers has TN 10 + its level. Knowing its feats has TN 15 + its level. Knowing its magical abilities (if any) has TN 20 + its level. Thus you can make up to four checks for each creature, to see what you know about its abilities, skills, feats, and magical powers. Once you know a fact about a monster, you should write it down on a note sheet to prevent your character from "mysteriously forgetting" information he had known just a few days ago. [...] I seperated what you can know about a monster. Knowing a monster's ability scores is probably the easiest, with skills and feats following, and last (and most difficult to discern) are any magical abilities. It may not be perfect, and may require some more tinkering, but I think it's a good step in the right direction.
Arcade 05-28-07, 09:26 AM	there was an article on the D&D page not too long ago about knowing about common monsters. For instance, trolls are common enough in stories and more common than their 5 Hd indicate. For cases like this, you can adjust the DC appropriately. For the dragons, you could see how well their DC does against a dragon of any age category. So if they pass the DC against a wyrmling, they can know that all red dragons are immune to fire, vulnerable to cold and breathe fire. But they have no knowledge of spell like abilities for older dragons or how large the breath weapons can get or that dragons cast spells. They'd need to pass the DC for higher age categories to learn that. The general idea behind DC of 10+HD is as a measure or rarity in the campaign world. High hit die creatures are generally more rare than low HD ones, but it's not necessarily true so you can adjust it. And for being in a library, you can definitely give the rolls a +2 bonus, and possibly even extra rolls if they spend multiple days in the library. hiring researches can give aid another bonuses. Also, my players consult sages who have good knowledge checks and libraries to find out this stuff.
Ecalsneerg 05-28-07, 10:10 AM	I was also thinking this could apply to a Ranger's Favored Enemy Class Feature--but I wasn't sure how to limit it (the periodicals on monsters comes out monthly, so failure means they can't roll against the same monster until next month). Perhaps for Favored Enemy, the ranger can roll once against the certain monster (of course, of a type that is one of his favored enemies) in his/her whole lifetime; success means he/she knows a little bit; failure means he/she knows nothing (but of course still gets the bluff, listen, spot, etc bonuses from Favored Enemy). This roll can be done for any monster, as long as the monster has not been rolled on before and is under one of his/her chosen favored enemies. Why would a Ranger get bonuses for Favored Enemy if he knew nothing about the monster? I've always assumed Favored Enemy gave you a working level knowledge of a monster. Personally, I advocate it giving bonuses to Knowledge checks relating the enemy in question, and giving, say a DC 5 or 10 level of knowledge on their favored enemies.
Kradlo 05-28-07, 10:47 AM	You can also use Knowledge/Monsters. But the DC is 20 plus the monster CR. There is no Knowledge (Monsters) skill. The Knowledge skills for identifying monsters is detailed in the PHB. In my campaign, I make adjustments to the DC based on commonality of the creature and other circumstances. A ranger that has Magical Beasts as his favored enemy gains a circumstance bonus on Knowledge (Arcana) checks to identify magical beasts equal to his favored enemy bonus. If trolls are a common threat in an area, the DC to identify them may be 5 lower, or even 10 lower, depending on how common they are. "Trolls? Yeah, they attack every winter, so we keep barrels of oil stacked by the city walls, and plenty of torches. That, and the king's wizard is right handy with fire spells." The GM is judge of what is and what is not common knowledge for his campaign.
Krusk 05-28-07, 11:59 AM	We use 10+HD, but if the enemy has less than 3 or 4 HD no roll is needed. Anyone can just know it. In the case of dragons where they would know younger forms are immune to fire, but know nothing about the older forms. I usually read the info i would give for the oldest form they would know about, and then tell them something like "but this one looks much bigger/older" so they get a general idea. Never had a problem with this system.