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Author Topic: Help me build a RPG Combat System  (Read 2519 times)

bahihs

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Help me build a RPG Combat System
« on: March 28, 2015, 03:13:36 pm »

This is the second part of my world-building escapades

Essentially, I want to create a custom combat system (really an entire homebrew, but we have to start somewhere) which fits well with the world. Unlike the world-building project, this is much more dependent on user suggestions and input and is more of a collaborative effort. I will try to write about the topics in order, but feel to suggest in whatever order you like.

Please give the suggestion in bold, and then its details. Italicize any mechanical stuff (numbers, dice rolls etc.). This keeps everything clear and orderly.

Here are a list of goals I'd like the combat system to have (in order of priority):
1. Realism
2. Small learning curve, but not shallow
3. Not too much crunch
4. Not too much book-keeping
5. Results should be based 70% on PC skills/stats, 30% on the Player's cleverness

Some limitations:

1. We may only use d6 die (why? because everyone has d6 and because they are easy to replace)
2. We may use a standard 52-card deck (if necessary)
3. No math beyond basic algebra and statistics

Here are the things we need to consider to build this system:

1. Before the battle
- Inherent biological characteristics (stats/abilities): This represents the maximum, inherent potential of a combatant
- Learned characteristics (skills/combat styles/techniques): The combination of applicable knowledge learned through experience and training
- Tools (weapons/armor/items): Involves the characteristics of the tools of combat, determined by its material and craftsmanship

2. During the exchange of blows
- Time (preferably "real-time", like GURPS or Riddle of Steel): Basically I'd like to have combat done in "time-slices" of arbitrary size, where actions occur according to the combatants speed
- Space (No tactical map will be used, so we need get creative): I won't be using a game map, so the spacial environment needs to be described in a concrete, usable way. Movement within this space, also goes here.
- Accuracy (Whether and where, the attack hits): One of the "big two" of combat, the other being "Force". Whether the blow hits is fairly easy to determine, where it hits is not so easy. I want to avoid book-keeping, but it is difficult to be realistic without combat locations.
- Force (The "hardness" of the hit): The other of the "big two", represents how much harm the blow does (the harm need not be physical, a strong or expert blow can knock a weapon away, or stun the opponent)
- Tactics (Elements which affect the above four; high ground, footing, visibility, numbers etc.): This is what separates combat from a mere skill check and what actually makes it interesting/deep. Everything from feinting to differences in terrain to trash-talking falls under this

3. After the exchange of blows
- Bodily harm (Wounds i.e damage to tissues and organs): The big question is how is this represented? HP? Wound Levels? Something else? And even bigger, how do we minimize book-keeping, despite the fact that this sort of harm is more permanent
- Mental harm (Shock from a hit, fatigue, fear, anger): Affects the next immediate exchange, but usually little else. Again, book-keeping kept to a minimum, how?
- Change in condition (caused by the above two; stunned, bleeding, knocked over, crippled etc.): These are the manifested effects as the above two accumulate.

4. After the battle
- Recovery through rest: Should really only work for small wounds (cuts, bruises, sprained muscles, muscle fatigue)
- Recovery through medicine (drugs, first aid, bone setting, surgery etc): For the vast majority of injuries. Medicine in Tsust ranges from primitive herbal-ism to powerful purified drugs, and advanced surgical techniques
- Recovery through magic (uncommon and expensive, but miraculous effects): For the severed limb, the catatonic, the paraplegic and the dead, party member. Usually is an entire adventure in itself

If you guys feel I missed something, go ahead and post it and I'll add it to the schema.


A few words about combat in Tsust.

Most combat will be between humans, as the world is human-dominated. Combat may also include beasts and creatures who are likely primitive and unskilled, but have evolutionary adaptations which make them dangerous (sharp teeth, strong limbs, claws, etc.). Other more exotic creatures, usually created as a result of magic, may or may not be sentient, but will almost always have some special ability or aspect making them unique (e.g ghosts cannot be harmed by normal weapons, ghoul's cannot move beyond the place they haunt etc.).

As above, combat should be realistic (or as realistic as it can be in a fantasy world) but should not be bogged down by numbers, book-keeping or rule-tracking. Death is a real thing, but not the be-all, end-all. Magic can be used to commune with ghosts, summon spirits, even bring back the dead, but often at great cost or risk. The PC will have "divine protection" (this is an actual in-world phenomenon which I will describe in the world-building thread), which entails some sort of "Fate Point" system giving them some laxity regarding death. However, few, if any, battles will be to the death. I wish to emphasize this point through the combat system (particularly the "Mental Harm" section). A group of bandits may scatter if their leader dies, animals tend to flee when they get injured and so do humans. But this holds true for the PC as well! Part of combat is learning to pick your battles and retreating when things seem to dangerous. To that end, no matter how strong the enemy, there is a way to get out or flee the situation. Deescalation (through speech, bribes, even begging) is important, and so is intimidation and mercy.

As for the mechanics itself, I am leaning toward a system which has great number of base characteristics (i.e stats) that are almost never used but that combine in different ways to create a smaller subset of characteristics which are used often (i.e derived stats). The former are set at birth and represent maximum potential, which are only changed by serious trauma (severed limbs, brain-damage, nerve-damage etc.), the latter are the day-to-day variables which change easily and temporarily.

Of course I am open to anything (within the limitations I stated above) and nothing is set in stone.
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bahihs

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Re: Help me build a RPG Combat System
« Reply #1 on: March 28, 2015, 03:16:21 pm »

Ok, so after some discussion with my players I've gotten some preliminary ideas for the system. It seems my players prefer "narration" above "gaming" and "simulation", which more less fits with our plan so far (minimal crunch and book-keeping). To that end, I've whipped up a semi-simple system which I plan to test this weekend. Tell me what you guys think and poke holes as much as possible.

*Since everything here is basically "mechanics" I'm not going to italicize anything

1. Before the Battle

Stats: Four stats, taken from GURPS: Strength, IQ, Dexterity, Health; values range from 3 to 18 (3 being abysmal, 18 being superhuman, 10 is average, 16 is peak of humanity). As well as 2 derived stats: Fatigue and Wounds which are derived from Health. The default fatigue (at a Health score of 10) is 3. 11-14 gets you to 4 (3+1), 15-17 gets you 5 (3+2) and 18 gets you 6 (3+3). Health may also contribute negatively to fatigue: if it is 9-6, fatigue = 2, 5-4, fatigue = 1 and a health score of 3, indicates the person is too unhealthy to move (catatonic or bedridden). 

Skills: Only 3 relevant combat skills: Weapon skill, Shield skill, Movement skill (Athletics, Acrobatics etc). Which range have a range of 4 values: untrained (+0), trained (+1), professional (+2), master (+3). These are directly added to the roll (explained below)

Tools: Items have "material" and "quality". Material indicates the substance the item is made from and is descriptive (e.g Iron, Steel, Titanium alloys, etc). Quality is a numerical indication of the item's effectiveness. Quality ranges from -5 (broken) to +5 (artifact) and this modifier helps determines damage (again, see below). All other weapon information (reach, weight, etc.) are done intuitively given agreement from the players and the GM. If there is no agreement, GM's word is final (the idea is that it never actually comes to this, since such factors are not going to be considered anyway).

2. During the exchange of blows

Time: Time passes in 1 second "slices" where every person take a single action one by one, attacks are resolved immediately before going on to the next person. Initiative is not determined by a roll (because its tedious and it takes too long) but by a simple comparison of IQ then Dex (if IQ is equal) and then a dice roll (if Dex is also equal). Extra actions are free as long they make sense within the time frame (the exception is speech, which takes up exactly one turn even though it may take longer than 1 sec; short yells and shouts are free however)

Space: Borrowed heavily from Fate Core system for this. Essentially the combat environment is described to the players based on what they can reasonably see and consists of "areas". To move from one area to another takes one turn. Combatants may only engage each other if they are in the same area (the exception is obviously ranged weapons, where common sense dictates). In theory one could just keep running away, but the limitation of fatigue prevents such chicanery.

Terrain is abstracted into a simple modifier determined by the GM at his discretion. A modifier must be given where it is sensible, but the GM decides how large the bonus is. The modifier may range from -5 to +5 to the target number only (never to the actual roll), and may exceed 18 (but never be below 3). Terrain will be further explored under "Tactics".

Accuracy: There are two questions that must be answered regarding this topic:
I. Do you hit?

This question is answered by a simple 3d6 roll, with the appropriate skill modifier (and any other modifiers) added to the roll (not the target number (TN)). An 18 or 17 (on the die) is a critical hit, a 3 or 4 (again, on the die) is a critical failure.

The target number against which this roll is compared is (11 + any pertinent modifiers (terrain, tactics etc.)), including any active defense of the opponent. There are three active defenses whose modifiers range from +0 to +3:
a. Dodge (every creature can do this): Determined by your dexterity. Dexterity of 10 gives you +0, 13 to 15: +1, 16 or 17: +2, 18:+3. If the dexterity is lower than 10 the modifier is negative: 3: -3, 4 or 5: -2, 6 to 9: -1
b. Block: Requires a shield. Determined by the shield skill. Ranges from +0 to +3 , as per the skill level.
c. Parry: Requires a ready weapon that can parry. Exactly equal to the bonus from the weapon skill. Ranges from +0 to +3, as per the skill level.

The target number may be greater than 18. Note here, that there is an emphasis on the skill over the stat, in that a skill will never result in a negative value. Of course if you posses the natural ability, you will forego skill for the better modifier (18 Dex, gives you the maximum +3 right off the bat, so blocking and parrying is unnecessary). However, if one is attacked multiple times before ones turn, one takes a -1 to a repeated dodge (but no penalty to a different defense) up to a -3. Furthermore, blocking or parrying a blow "un-readies" the weapon or shield, making it unavailable for a subsequent block or parry. This means fighting multiple enemies at once will almost certainly result in death. And thus, bottle-necking opponents and other such tactics are essential to combat. 

II. Where do you hit?

This question is answered by the player himself using only narration. The GM then decides an appropriate modifier based on the size of the target chosen and adjusts the TN accordingly. Here the modifier may range from +7 to +0, where +0 is the default target of the torso (if the location is unspecified, the default is assumed). 

Force: The central question of this section is: "How hard do you hit?". To answer this question we only use comparison of number-values. We do not make any additional rolls, but use a simple formula to determine damage. The formula is:

Damage= (Accuracy roll - TN)+(Weapon mod - armor mod)

The accuracy roll refers to the only roll made in combat, which is the 3d6 spoken of in the previous section. Weapon mod, refers to the modifier derived from the quality of the weapon. However, this modifier only applies if the material of the weapon is equal to or better than the material of the armor (i.e the weapon can actually penetrate the armor), otherwise this modifier is +0. Similarly the armor mod is simply the quality of the armor, and it is always applied (regardless of material). Note here, that decent quality armor is very powerful (especially if made of a good material) but is aptly balanced by making it prohibitively expensive. Iron is a scarce commodity in Tsust, and steel has a near-mythical rarity (titanium alloy's are a recent discovery as well and provide an alternative to steel). Common metals include copper alloys such as bronze or orichalcum (cupronickel), but armor with iron-like hardness, made from biological components, are far more common. Examples include Khat armor (made from the bark of the Khat tree) and !ung Silk vests, (made from the !ung plant). However, good materials are much more likely to be fashioned into weapons rather than armor (since less metal is needed). Furthermore, armor may be completely nullified by simply aiming for areas which are not armored (or aiming for "chinks" in the armor, which is much more difficult). Therefore the PC's should tread lightly!

Tactics: Tactics are an overarching term for anything which modifies the target number for the accuracy roll and is not an "Attack", "Defense" or "Move" maneuver. Tactics includes the concept of terrain advantage and is more or less free-form. The exception is bottle-necking, which confers no modifier but reduces the number of enemies that can attack the combatant at once. Tactics are left up to the players to create and play with and the GM to judge. A few tactics are given here for illustration:

- Feint: Compare weapon skill, then IQ (if wep skill is equal) then Dex (if IQ is equal), then roll a d6 (if Dex is also equal). If the attacker wins, his feint is successful and the next hit gets a -1 to hit TN (only in the next turn, it is nullified if the attacker chooses not to attack in the next turn). The attacker may do this up to 3 times for a maximum of -1 to the accuracy TN.
- High Ground: Whoever has high ground gets a -1 to the accuracy TN, and +1 to TN when defending
- Counter: Instead of defending an attack, the combatant compares his Dex (then his weapon skill, if equal; then rolls a die if wep skill is equal) to his opponent's. If he wins, he immediately makes an accuracy roll for an attack (modifiers are computed as usual) before the opponent's attack is resolved. If the combatant hits, he does double damage. If he misses, the opponent's still unresolved attack, will do double damage (if it hits), otherwise the attack is resolved normally.
- Aim: Every turn spent aiming gives a -1 to the accuracy TN. The enemy must not have moved to a different area while aiming, otherwise the aim is nullified. Can be used for both melee and ranged. In the case of ranged, if the attack is not aimed, the combatant takes a +1 to his acc TN.

3. After the exchange of blows

Bodily Harm: The wound system is basically stolen from Fate Core. The fatigue stat, which is derived from the Health stat also represents the number of wounds that can be sustained before things get serious. Like Fate, players have "boxes" ranging from 1 to 6 which are "ticked off" as damage is taken. The number of fatigue points determines how many boxes a PC gets. The amount of damage a box absorbs starts from 1 up to the fatigue number. This seems a bit a complicated as I write it (it might just be my sleep deprivation) so here's an example:

Health score = 14 (+1)
Fatigue = 4 (3+1)
Wounds = 1   2   3   4

Each number for wounds, represents a "box" which can absorb that amount of damage (e.g the 4-box can absorb 4 damage), to use a box, it is simply ticked off. That box then, cannot be used for absorbing subsequent blows. The boxes are unticked again after a period of rest and repose (see last section). Unlike Fate, multiple boxes can be used to absorb a single hit. If a hit does more damage then can be absorbed (even by a single point) a consequence is taken which immediately ends the fight. The consequence is a grievous injury which may result in death if untreated, but at the very least results in a cease to hostilities. Injuries such as this include: decapitation, evisceration, permanent blinding, breaking of bones, severing of limbs, serious damage to several internal organs, damage to vital organs (heart, lungs, etc.), excessive bleeding and so forth. These injuries are determined by the the location of consequence-yielding hit (if you hit someone in the leg, you more are likely to sever a limb than blind them).

Consequences also require a much longer time to heal and are often irreparable without the intervention of a surgeon or healer. Finally, only a single consequence is taken (unlike Fate Core where you may take up to three) before the fight ends. So tread lightly!

Mental Harm: Mental harm is manifested as fatigue. Fatigue works relatively simply, every action costs 1 fatigue point. At 0 fatigue points, the player cannot take any action (he must catch his breath first). Doing nothing recovers 2 fatigue points per turn. Only actions which reasonably tire the body cost fatigue points (e.g moving, attacking, tactical maneuvers, etc.), whether an action requires fatigue points is left up to the GM to decide.

Other types of mental damage include taunting, negotiating or intimidating. In each case, narration takes central point. If a contest of wills needs to be resolved, we simply compare the relevant skill and stat (IQ, speech skill, Strength for intimidation, etc.) adding any relevant modifiers for the first time and make a skill roll for every subsequent try (this type with a penalty to the TN due to having failed once already). This is only necessary when the result of such an action is more or less unclear (i.e don't try to convince animals or undead). Finally speech costs no fatigue but does cost your turn (if in combat).

Change in Condition: Basically covered in the first two parts of this section

4. After the battle

Recovery: There are two things that a player can recover from: minor wounds and major wounds. Major wounds are those derived from consequences and require surgical or magical intervention to fully cure. Minor wounds are the wounds absorbed by the wound-boxes. The wound-boxes remain "ticked" until the player gets adequate and sustained rest. Every day of rest returns a wound box, starting from the smallest ticked box to the largest. Medical care (treatment by someone with an appropriate skill) while resting bumps this by the skill level modifier (e.g medicine +2 returns 3 wound boxes a day instead of 1). Magical effects are usually instantaneous, but are hard to obtain (too costly). A major wound cannot be healed through rest alone and its effects are manifested through narration (blindness, severed limb etc.) first, and if necessary through a penalty to the health stat.
« Last Edit: April 01, 2015, 06:26:06 pm by bahihs »
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Pencil_Art

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Re: Help me build a RPG Combat System
« Reply #2 on: March 29, 2015, 01:56:03 am »

PTW.
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Urist Arrhenius

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Re: Help me build a RPG Combat System
« Reply #3 on: March 30, 2015, 12:16:04 pm »

ptw
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bahihs

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Re: Help me build a RPG Combat System
« Reply #4 on: March 30, 2015, 10:06:28 pm »

Added a sample combat system as a trial run.

Also I was curious, would anyone in the forums be interested in playing this as a forum game (very much possible since it takes a minimalist approach to materials)? Would give me a chance to try out the world of Tsust before I play face-to-face.
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Pencil_Art

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Re: Help me build a RPG Combat System
« Reply #5 on: March 31, 2015, 12:34:42 am »

Might try it out.
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Urist Arrhenius

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Re: Help me build a RPG Combat System
« Reply #6 on: March 31, 2015, 07:55:14 am »

I'd play if it were exploration based. Probably not if it was just a grind.
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bahihs

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Re: Help me build a RPG Combat System
« Reply #7 on: March 31, 2015, 09:36:58 am »

I'd play if it were exploration based. Probably not if it was just a grind.

Don't worry, although I've focused on the combat system here, the game is more about character development and adventuring than it is mindless dungeon-ing. 
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IndigoFenix

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Re: Help me build a RPG Combat System
« Reply #8 on: March 31, 2015, 11:52:05 am »

Quote from: bahihs
no matter how strong the enemy, there is a way to get out or flee the situation. Deescalation (through speech, bribes, even begging) is important, and so is intimidation and mercy.

Since 'social' actions are going to play a role in combat, have you considered using them as pseudo-attacks?  By this, I mean using social skills as actual abilities that have their own stats and can influence an opponent's stats in combat.  To this end, I would suggest modifying the use of the Fatigue system by adding a Willpower modifier to it.

Willpower, in this case, is very similar to your description of fatigue, but more flexible.  Similar to how, in traditional (unrealistic) RPGs, magic can quickly heal wounds during combat, Willpower could quickly be raised or lowered during combat through social actions and would have a major effect on a character's ability to fight effectively.  "True" fatigue - as in, the absolute limit of a body's capability - would still exist, but would only have a real chance of actually running out if the character was fighting at their absolute maximum potential, like during a prolonged adrenaline rush.

For instance, each character can have several personality-based stats, like Intimidation, Friendliness, or Shrewdness.  In combat, they could use any of these stats in particular actions (for instance, appealing to the opponent's mercy could be a 'social attack' based on the Friendliness stat and could lower the willpower of the opponent based on associated 'social defensive' stats, such as 'coldheartedness' and 'rage', while Intimidation could lower the willpower of the opponent based on their 'self-confidence' but could also increase their 'rage' if the move fails).  Similarly, you could use 'social buffs' like encouragement and rallying cries to increase the willpower of allies.  Basically, psychological effects could have a physical impact on both PC and NPC skills, and altering a target's mental state could take the place of that cheap magic takes in other RPGs.

Willpower and focus could be more important than bodily damage in fights between similarly-leveled opponents.  Between opponents of similar levels, most attacks would be blocked or dodged, but defending against attacks would cost 'will points'.  So psychological attacks and buffs would be functionally very similar to physical ones when determining absolute victory and defeat.  Once a character's willpower/focus had been lowered enough, physical damage would start to take effect (although a non-lethal physical injury could potentially stimulate an adrenaline rush, "healing" their non-physical damage and putting the character back in the fight).

bahihs

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Re: Help me build a RPG Combat System
« Reply #9 on: March 31, 2015, 09:08:00 pm »

Quote from: bahihs
no matter how strong the enemy, there is a way to get out or flee the situation. Deescalation (through speech, bribes, even begging) is important, and so is intimidation and mercy.

Since 'social' actions are going to play a role in combat, have you considered using them as pseudo-attacks?  By this, I mean using social skills as actual abilities that have their own stats and can influence an opponent's stats in combat.  To this end, I would suggest modifying the use of the Fatigue system by adding a Willpower modifier to it.

Willpower, in this case, is very similar to your description of fatigue, but more flexible.  Similar to how, in traditional (unrealistic) RPGs, magic can quickly heal wounds during combat, Willpower could quickly be raised or lowered during combat through social actions and would have a major effect on a character's ability to fight effectively.  "True" fatigue - as in, the absolute limit of a body's capability - would still exist, but would only have a real chance of actually running out if the character was fighting at their absolute maximum potential, like during a prolonged adrenaline rush.

For instance, each character can have several personality-based stats, like Intimidation, Friendliness, or Shrewdness.  In combat, they could use any of these stats in particular actions (for instance, appealing to the opponent's mercy could be a 'social attack' based on the Friendliness stat and could lower the willpower of the opponent based on associated 'social defensive' stats, such as 'coldheartedness' and 'rage', while Intimidation could lower the willpower of the opponent based on their 'self-confidence' but could also increase their 'rage' if the move fails).  Similarly, you could use 'social buffs' like encouragement and rallying cries to increase the willpower of allies.  Basically, psychological effects could have a physical impact on both PC and NPC skills, and altering a target's mental state could take the place of that cheap magic takes in other RPGs.

Willpower and focus could be more important than bodily damage in fights between similarly-leveled opponents.  Between opponents of similar levels, most attacks would be blocked or dodged, but defending against attacks would cost 'will points'.  So psychological attacks and buffs would be functionally very similar to physical ones when determining absolute victory and defeat.  Once a character's willpower/focus had been lowered enough, physical damage would start to take effect (although a non-lethal physical injury could potentially stimulate an adrenaline rush, "healing" their non-physical damage and putting the character back in the fight).

lol, you beat me to the edit. I actually had a similar thing planned but it was late last night when I updated the thread so I forgot to put it in. I'll put it in sometime tomorrow. However, let me just address your suggestion:

Its pretty good, but I think its bordering dangerously over the "book-keeping" precipice as you'd have to keep track of willpower in addition to fatigue. Instead, I'm planning to abstract all of this into narration by the player and a simple comparison of stats (so there will probably be a willpower stat). If there is a contest of some sort, skills will initially be compared:

e.g I tell you to back down from the fight, giving a logical argument for why you should (using speech skill; as opposed to intimidation, which would use the Strength stat). To resist this argument you'd compare your own speech skill (or IQ, whichever is higher) to mine and if you win, you scoff/spit in my face. This would cost me a turn (if in combat already) but no fatigue. This can only work if the narration fits (don't try to convince drug-addled muggers, undead, or animals) If I try to convince you again, I rollmy skill with an appropriate penalty (for having failed once already) to the TN. I can do this as many times as I like, taking  a higher penalty each time I fail (and of course giving up my turn to talk).

Now, besides skill in speech-craft, the situation can also influence negotiations. Calmly telling you're opponent to back off when he is lying in a pool of his own blood or his leader's head is on a pike, tends to be more convincing than when you are surrounded are drawn bows. These sorts of situational influences are accounted for as a modifier to the TN (as everything else) determined by the GM for the skill roll (or simply added if doing a comparison of attributes).

Finally having personality traits, I have found, tends to limit roleplay. Also, I can see these quickly getting out of control, where you might have too many numbers to keep track of. Instead, we can just use common sense and narration to decide how cold-hearted or enraged or merciful the enemy is (and if numbers are absolutely necessary, we have our handy TN modifier).

Does that make sense? If not, hopefully I can make it clear when I update the "Mental Harm" portion of the system.
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bahihs

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Re: Help me build a RPG Combat System
« Reply #10 on: April 01, 2015, 06:28:10 pm »

Added the bit about negotiations in the combat system. Decided not to make an additional stat for willpower, instead just comparing existing skills or stats.
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