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SkillTwenty

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SkillTwenty

Status - Basic draft written up (except for skill descriptions which will come sometime soon). Feel free to comment (at the end).

If anybody feels motivated to make a character sheet (word or pdf) please feel free and mail it to me (lawrance@maths.uct.ac.za).

SkillTwenty is the simplified D20 system for use in the EmailTop game, Asalon Four. It is subject to revision.

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1. Introduction

The basic mechanic of the D20 system is really nice and straightforward. However, the D20 Modern game is made unnecessarily complicated (in my opinion) by adding classes, professions, specialty classes, feats, talents, etc. The aim of the SkillTwenty is to simplify the D20 system as much as possible by reducing everything to abilities and skills, whilst everything is resolved using ability and skill checks.

What are the advantages of a simpler system? The obvious answer is that new players can learn it more easily. Another reason is that character creation is a lot simpler and quicker (15 minutes instead of 3+ hours), especially for NPCs? (5 seconds for non-heroic NPCs?). And a final reason is that a simpler system allows you to focus on the story more than the system - after one session, a GM shouldn't need to refer to the rules again.

Disadvantages? The main one is that fewer situations are specifically catered for - a GM is going to have to make ad hoc rulings on the fly. Another disadvantage is that characters don't receive any special powers as they level up. Instead they just become better at what they've already been doing (although they could still pick up new skills, it's not quite the same as D20's class features).

Changes from D20

• Only 5 abilities (Str, Dex, Int, Wis, Cha), with Consitution being absorbed by Strength. The reason for this is that Con would only be relevant for one skill, making it a very unimportant ability.
• Attacks are now skills. Your base attack bonus is instead ranks purchased in a specific weapon's skill. This is both more realistic (you don't get better at all weapons over time, but only in the ones you train in) and simpler.
• Armour Class (or Defence Class) is now a skill (Defence). A character's Defence score is the same as if he'd rolled a 10 for his Defence check. This is similair to the NPC's automatic 10's described in the NPC section.
• Saves are now incorporated by skills that have other uses: Fortitude save is now included in the Toughness skill, Will save in the Concentration skill, and Reflex save in the Reactions skill.
• Initiative is based on the Reactions skill.
• Hit Points never become very high. Most non-combat characters will only have a 10 hit point maximum for an entire campaign. Even combat characters can only increase their hit points by 1 hit point per level. Maximum hit points are given by an automatic 10 on a Toughness check.
• Dropping to 0 hit points kills unimportant characters, and takes PCs? and other important characters Out of Action - effectively out of a combat normally by falling unconscious. These characters die when their current hit points drops to the negative of their maximum hit points. Their is no hit point loss or stabilisation check for being at negative hit points, though permanent damage could be the result if an Out of Action character doesn't receive serious medical attention.
• Character's skills start off much higher than they normally would, but improvement is slower. Although character levels aren't formally defined, they effectively occur once every 6 sessions. When going up a level, a character can increase one ability score by 1, or 6 skills by 1 rank.

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2. Character Creation

Abilities

There are 5 abilities:

• Strength (Str)
• Dexterity (Dex)
• Intelligence (Int)
• Wisdom (Wis)
• Charisma (Cha)

The average score for each ability is 10. Most humans have ability scores from 8 to 13. Exceptional characters, such as the heroes, can have abilities as high as 18 ... and possibly even higher with experience.

A player has a total of 20 ability points to purchase the scores for his abilities. The cost of each ability score is given below. For each ability write the score next to the ability name on your character sheet.
| Score | Cost | Score | Cost | 8 | 0 pts | 14 | 6 pts | 9| 1 pt| 15| 8 pts | 10| 2 pts| 16| 10 pts | 11| 3 pts| 17| 12 pts | 12| 4 pts| 18| 14 pts | 13| 5 pts

Each ability score has an associated modifier that you also need to fill in on your character sheet.
|Score|Modifier |8|v-1 |9 |10|v0 |11 |12|v+1 |13 |14|v+2 |15 |16|v+3 |17 |18|v+4 |19 |20|+5

etc.
!! Skills
There is an unlimited number of skills that a player can choose from for his character. Presented below is a list of possible skills to choose from. Note that your campaign may have a different set of skills to choose from. You may also create your own skills, subject to your GM's approval.
Some of these skills require a more precise subskill to be chosen. For example the Knowledge skill is really a group of skills such as Knowledge: Business, Knowledge: Religion and Knowledge: Science. Ranks must be purchased individually for each different Knowledge subskill.
A player should start by choosing 3 specialty skills. These represent the skills that a player's character has specialised in.
A player has a total of 48 skill points to purchase ranks for his character's skills. All skills start at 0 ranks, and the cost of one rank is one skill point. However, there is a maximum rank to which you can raise your skills. For specialty skills, this maximum rank is your total skill points / 6 (i.e. 8 for starting characters). For all other skills, this maximum rank is your total skill points / 12 (i.e. 4 for starting characters).
Combat Skills	border=1
Tech Skills
Dex	<Ranged Weapons	(weapon type)	Int	<Computer Use

|Str|<Melee Weapons|(weapon type)|Int||border=1

<Tinker
Dex	<Defence|Dex|<Drive|(vehicle type)

|Str||border=1

<Toughness	Int	<Spaceship Operation	(spaceship role)
Wis		<Concentration	Dex	border=1
<Fighter Pilot
Dex		<Reactions	border=1
Str		<Unarmed Combat	border=1
Perception Skills
	Wis	border=1
<Listen
Career Skills	Wis	border=1
<Spot
Int	<Craft	(craft item)	Int	<Search

|Wis|<Profession|(job)||border=1

Cha	<Perform	(performance type)		Interaction Skills

|Int|<Knowledge|(knowledge category)|Cha||border=1

<Bluff
	Cha	border=1
<Diplomacy
Adventure Skills	Cha	border=1
<Intimidate
Str		<Climb	Wis	border=1
<Sense Motive
Wis		<Survival	Cha	border=1
<Gather Information
Wis		<Treat Injury	border=1
Str		<Jump	border=1
Underworld Skills
Str		<Swim	Cha	border=1
<Disguise
Dex		<Balance	Dex	border=1
<Escape Artist
Cha		<Handle Animal	Int	border=1
<Forgery
	Dex	border=1
<Hide
	Dex	border=1
<Move Silently
	Dex	border=1
<Sleight of Hand
border=1
Individual skills are described in section 3

Note that each skill has an associated ability. To calculate how proficient you are at a skill add your ability modifier (for the associated ability) to the number of ranks you have in that skill. This number is referred to as your skill modifier.

Hit Points and Defence

There are two more items that need to be filled in. Your maximum hit points is equal to 10 + your character's toughness modifier. Your defence score is equal to 10 + your character's defence modifier.

Equipment

This is highly dependant on the campaign. Many characters will have at least one weapon. They should find out all the information they need for the weapon from the GM, or from the weapon table in the combat section (if that is being used in the campaign).

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3. Skill Descriptions

Skill descriptions will be given when I actually have the time - in the meanwhile the following are the ones that need a bit of explanation. Comparison to D20 (D&D) is given.

Weapons
Weapon skills are either Ranged or Melee. Correspond to Attack Bonus of D20.

Defence
Armour Class of D20. Difficulty Class (DC) for weapon skill checks.

Toughness
Hit Points = 10+Toughness. Also equivalent to Fortitude Save of D20.

Concentration
Used for magic, psionics, etc. Also equivalent to Will Save of D20.

Reactions
Used for initiative at the start of combat. Also equivalent to Reflex Save of D20.

Computer Use
Anybody can use a computer, but those with this skill can also hack computers, bypass security systems or simply know where to download the best biochemical weapon recipes.

Tinker
This skill is basically a catch-all mechanical skill, describing everything from disarming bombs to repairing engines.

Spaceship Operation
A spaceship is a complex piece of equipment. Whilst any spacefarer knows the rudiments of operating the various aspects of a spaceship, normally a spaceship is run by a number of specialists each with their own area of expertise. These are the subskills labelled (spaceship role). The following are examples of subskills for this skill:

• Pilot
• Gunner
• Navigation
• Captain

Fighter Pilot
Flying a spaceship is very different from flying a one-man space fighter. The best fighters are those with extraordinary hand-eye co-ordination and quick reflexes.

Skill1

Skill2, etc.

Using a Different Skill Set

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4. Ability and Skill Checks

SkillTwenty's Basic Mechanic

Whenever the success of a character's action is in doubt, the character's controller needs to make a Skill check. Here is the procedure for making a skill check:

• The GM decides what skill is being used. Sometimes no skill is appropriate and so a pure Ability check is used.
• The GM chooses a target number called the Difficulty Class (DC). He does not need to tell the players what the DC is.
• The player rolls a D20. His character succeeds if D20 roll + skill modifier >= DC (or D20 roll + ability modifier >= DC)

Example 1: A player says he wants his character, Charlie, to try and climb the wall surrounding the guard compound. The GM tells the player that he needs to make a Climb check. The GM decides that the wall is in good condition, fairly smooth and very high, so the DC is a challenging 25. Charlie's Climb skill modifier is +8. He rolls a D20 and gets a 15. His total is 15+8=23 which is less than 25. So Charlie fails to climb the wall. The consequences of this failure is up to the GM - possibly he falls from a height and sustains some damage.

Example 2: A log has fallen on Bob's leg, trapping him underneath. Andy rushes to Bob's assistance and tries to lift the log. There is no appropriate skill, so the GM decides that a pure Strength check needs to be made. The log is heavy but easy to get a good grip on. The GM decides that the DC is 18. Andy's strength modifier is +3. He rolls a 17 on a D20, so his total is 17+3>=18, so he succeeds in lifting the log.

Roll Modifiers

Sometimes modifiers need to be applied to the player's roll because of specific circumstances. In example 1 above, Charlie might have some special climbing tools. When using the Ranged Weapons (standard firearms) skill, a character's rifle might have a telescopic sight or his target might be in very close range. All of these situations will give the player a bonus to his roll. A pistol in poor condition will give the player a penalty to his roll.

Advantages (such as specialised equipment or beneficial circumstances) give a player a +2 bonus to his roll. In extreme conditions a greater bonus might be applied (for example exceptional equipment made by an alien race).

Disadvantages (such as poor equipment or hindering circumstances) give a player a -2 penalty to his roll. Extreme conditions might result in a greater penalty.

Multiple bonuses and penalties should be added together, to give the final roll modifier.

Deciding on Difficulty Classes

In some situations, you can work out the DC exactly. More often, though, you will need to make a rough estimate.
| Difficulty | DC | Trivial | 0 | Easy | 5 | Moderate | 10 | Challenge | 15 | Difficult | 20 | Very difficult | 25 | Almost impossible | 30 Most DCs? should be 15 or more. DCs? of 5 or less are for mundane tasks and so do not normally need a roll. A DC of 10 is mundane for characters who not have training (i.e. high ranks) in that skill.

Ability check DCs? should be 5 less than Skill check DCs? to compensate for the fact that ability modifiers are lower than skill modifiers.

The DC can be worked out exactly when the character is opposing the action of an NPC. In that case the DC = 10 + NPC's skill modifier. For example, Donald is trying to bluff his way into a high security compound. The guard, an NPC, has a Sense Motive modifier of +4. Donald has to make a Bluff check against DC = 10 + 4 = 14.

This DC can be adjust for circumstances as well. If the guards are particularly suspicious a +5 adjustment could be made to DC (i.e. increasing the difficulty be one level on the chart above).

Untrained Skills

If a character has 0 ranks in a skill he is considered untrained in that skill. The effect of being untrained depends on the skill.

Some skills require specialist training to even use. For example, Spaceship Operation (pilot) probably requires years at a space academy to even become able to understand the controls (though your campaign may differ). In this case, if a player who is untrained in Spaceship Operation (pilot) tries to pilot a large spaceship, he automatically fails.

On the other hand, some skills are so common, that we end up using them all the time. Some people have specialist training or extra practice in that skill which gives them their skill ranks, but not having training doesn't result in any disadvantage. Skills like this are Listen, Spot, Search, Climb, Jump, Swim, Defence, Toughness, Concentration and Reactions.

Most skills, however, require some training or practice to be competent at them, but being untrained doesn't stop you from trying. If you are untrained in a skill of this type will result in a -2 modifier being applied to your roll. For example, anybody can fire a pistol, but if you are untrained in Ranged Weapons (standard firearms), apply a -2 penalty to your roll.

The GM has the final say on the consequences of being untrained in a skill. If in doubt, apply the -2 penalty.

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5. Combat

Initiative

Combat is divided into rounds. Within each round characters act in the same order. To determine this order, at the beginning of combat, each character makes a Reactions check. Whoever gets the highest result goes first, followed by the person who got the second highest, etc (Split equal results randomly with another Reactions check whenever it makes a difference).

The exception to this rolling for initiative order, is when one group surprises another. The group that has the element of surprise automatically goes first. If its necessary to determine the order within each group, they can roll initiative order.

A character who is acting early in a round, can choose to delay and act at a later point in that round. However, for the rest of the combat, the character must act at this later point. One can even delay one's action into the next round. This is exactly equivalent to the first case, due to the cyclical nature of the initiative order.

Attacks

One round lasts approximately six seconds (10 rounds/minute). An action in that round is anything that can reasonably be accomplished in six seconds. Under normal circumstances a character can make one effective attack in a single round.

An attack is made by making a Skill check of the type of weapon being used. For example, shooting with a pistol requires a Ranged Weapons (standard firearms) check. The DC of the check is the target's Defence score. If the check succeeds, the attacker rolls dice according to the damage dealt by the weapon. This total is subtracted from the target's current hit points. Melee weapons and thrown weapons do additional damage equal to your Strength modifier.

Out of Action

When a character reaches 0 or fewer hit points, he is Out of Action and can no longer contribute to the combat. A character in this state is normally unconscious, but may instead have lost a limb or be semi-conscious and dying. A character who is out of action is helpless and may still be attacked (although the morality of this is dubious, and a better strategy is normally to focus on the still active opponents) and lose hit points normally.

A character dies when current hit points <= -(maximum hit points). So a character with Toughness 5 has a maximum of 15 hit points. He's out of action when his current hit points drops to 0 and dead when his current hit points drops to -15.

Recovery

With normal, non-strenuous activity, hit points are recovered at a rate of 1/day. Complete bedrest or surgery can help one recover at a faster rate depending on the available technology.

However, a character who was taken Out of Action by a lethal weapon (such as a sword or pistol) has been critically wounded and will need surgery to recover properly. If surgery is not obtained more or less immediately, then there are lasting consequences - permanently damaged limb or something similar resulting in a decrease in the character's ability scores.

Sample Weapons and Armour

The most important attributes of a weapon from a sytem point of view, is the skill needed to use it and the damage it deals. Some weapons might have other special attributes to differentiate them and give them flavour.

The standard melee weapon should deal 1d6 damage, and the standard non-firearm ranged weapon should deal 1d6 damage. The standard firearm should deal 2d6 damage.

Here follows an example of weapons for a typical sci-fi setting.

| Weapon | Type | Skill | Damage | Dagger | melee | Melee Weapons (Daggers) | 1d4 | Sword | melee | Melee Weapons (Swords) | 1d6 | Laser Rapier | melee | Melee Weapons (Energy Weapons) | 1d8 | Bow and Arrow | non-firearm ranged | Ranged Weapons (Bows) | 1d6 | Pistol | firearm ranged | Ranged Weapons (Standard Firearms) | 2d4 | Rifle | firearm ranged | Ranged Weapons (Standard Firearms) | 2d6 | Laser Pistol | firearm ranged | Ranged Weapons (Energy Weapons) | 2d6 | Heavy Laser Gun | firearm ranged | Ranged Weapons (Energy Weapons) | 2d8

Armour generally provides bonuses to your Defence skill in certain cicumstances. This is the same as an equipment modifier, and should typically be +2, +4 or +6, depending on the appropriateness of the armour.

Here follows an example of armour types in a typical sci-fi setting.

| Armour | Defence Modifier | Special | Chainmail | +6 against primitive weapons | +2 against firearms, and +0 against energy weapons | Kevlar | +6 against firearms | +2 against most other weapons, and +0 against energy weapons | Reflective Armour | +6 against laser weapons | +2 against most other weapons

Example Combat

George encounters his arch-nemesis, Harry, in an alley one night. They both draw weapons preparing to fight. They both make a Reactions check. George gets a 17 and Harry a 12, so George goes first. He fires his Pistol at Harry. His Ranged Weapons (standard firearms) modifier is +8. He rolls a D20, adds 8 and gets a result of 15. Harry's Defence modifier is +4, so his Defence score is 14 (=10+4). Since George's skill check was higher than Harry's defence, the bullet hits, and George rolls damage: 2d4 for a pistol. He rolls a 5, and so Harry loses 5 hit points from his total of 11 (he has a Toughness modifier of +1), leaving him with 6 hit points until he is out of action.

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6. NPCs?

Characters can be divided into three groups: ordinary, important and heroic. The PCs? are examples of heroic characters, and major villains and allies are also heroic characters. Other NPCs? are divided between ordinary characters and important characters.

Ordinary NPCs?

These are the bulk of characters the players will encounter. Ordinary characters have the ability scores (12/11/10/10/8) in some order - i.e. one positive modifer and one negative modifier. Ordinary characters have exactly 4 ranks in each of 3 skills. So to create an ordinary character, a GM need only choose which ability is a character's strongest, which is his weakest, and what 3 skills are appropriate.

Example: Thug (+Str, -Int, Melee Weapon (dagger) +5, Intimidate +4, Toughness +5)

Ordinary NPCs? die when they reach 0 hit points instead of being Out of Action.

Important NPCs?

Leaders or characters with noteworthy plot interest are Important NPCs?. They have the ability scores (13/12/11/10/8) in some order - i.e. 2 positive modifiers and one negative modifier. Important characters have exactly 6 ranks in each of 3 skills. A GM creates an important character in the same way as ordinary characters.

Example: Mean Mike, street gang boss (+Str, +Dex, -Int, Ranged Weapon (standard firearm) +7, Intimidate +6, Defence +7).

Important NPCs? are Out of Action at 0 hit points and dead when hit points = -(maximum hit points).

Heroic NPCs?

Heroic characters are created using the same rules as a player character. They are Out of Action at 0 hit points and dead when hit points = -(maximum hit points).

NPCs? using Skills

Most of the time, it is not necessary to roll for an NPC using his skills. Instead assume that a roll of 10 is made. So, for example at the start of combat, an NPC with a Reactions modifier of +4, would get an automatic Reaction check of 14.

The exception to the automatic 10 rule is when a fixed number is being aimed for. For example, in combat making an attack requires a role against a fixed Defence score. The attacking NPC should make an attack role just the same as a PC would.

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7. Character Advancement

For long-term campaigns, it is often desirable for players to see their characters improve with time. This is done by awarding experience points at the end of each session or adventure. Typically 1 experience point per session, with a bonus after major accomplishments, is sufficient.

Experience points can be spent to either improve skills or ability scores.

• One experience point buys one skill point. This increases your total skill points (possibly increasing your skill maximum ranks) and allows you to purchase a rank in a skill (though you can't exceed that skill's maximum rank).
• 6 experience points allows you to increase an ability by one (with no upper limit).

Experience points need not be spent immediately, and are normally spent in groups of six, as this allows you to increase your specialy skill maximum rank by 1 (Note that you can also convert experience points to skill points and not spend the skill points immediately).

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Comments

If you want tables to work, uncheck "Use new markup" when saving. - MyrdemInggala - Thanks!

I'm particularly interested in thoughts on the following:

• No Constitution ability
• Current skill list (thoughts on skills to add, remove, recombine, etc.)
• Low hit points
• Any point where things become too complex to just pick up and play

d@vid May 29 2003

(with Tim's comments on these comments in italics)

my major comment is the one below about the color of the game being
the backbone to the very simple ruleset, ie the campaign must be clearly defined* before play to help pick and interpret skills & their
use

• this does not mean in excrutiating detail

no con: yeah, whatever, and about time too

saves as skills: feels funny, but makes sense (Saves aren't skills by themselves, but incorporated into other skills - Fortitude is Toughness which is used for hit points as well, Reflexes is Reactions which is used for Initiative, and Will is Concentration (??) which is a standard skill anyway.)

how about alternity style initiative/action rounds? not that we're
going to have blow-by-blow email combat, but if there's some reason to use initiative in email, this may be a more efficient way to
run it (and in tabletop as well) (Alternity initiative is nice and more interesting but more complicated - hence not preferred. House rules of this sort are always possible.)

tangental oh-my-cleric-levels idea: who the hell said that any
initiative/round based system had to have microseconds as rounds? why not minutes? why not years (for intense decades-long action
between indefinitely prolonged super races)? chrono-scalability! (6 seconds is the default round length as per normal D20 system - no reason not to change it based on setting. Space combat using fighters probably would use a longer time frame.)

to kind-of simulate classes, perhaps story events can grant characters
special skills at automatic high ranks (or increase existing skills but for a neat in-game reason); with a stripped-down system like
this (which I would say is either loosely Simulationist or Narrativist depending on how you run it: TheWindow? but without the laws/tenets) I
think it's more important that story color explains or expands the numbers, than that there are rules for the numbers

(Kind of like in the game at the moment, Timefreeze Inc (see MiniCampaigns), where I gave characters the feat Personal Firearms for free because they went through a basic pistol use training course - equivalent to giving free skill ranks to characters. But for special skills, i.e. special powers there probably needs to be a bit of a system. So a thief-like character joins an assassin's guild and learns the Sneak Attack skill (4 ranks). How does this then work? Could come up with a bunch of ad hoc rules for these special skills, but...)

how is skill penumbra defined? eg, using my Sword skill to know about
swords as well as use them, and generally eliminating extraneous Knowledge skills? (although obviously Knowledge(History) and Melee(Sword) would
reveal different details about the same sword, but as a professional Swordsman I would expect to get something decent with Melee(Sword))
suggestion: a skill can be used when it applies directly, or a -2 or other untrained penalty can be applied (ie, it's better than having
no relevant skill at all) another suggestion: given that speciality skills should effectively
define a character's "class", be more lenient with these (ie, specialised Melee(Sword) suggests the character is a mercenary or
something, and possibly would have special knowledge about the sword's history, non-specialised Melee(Sword) is just a guy who
swings a sword

(Okay - the idea is that the skill set depends entirely on the campaign. The default skill set given is for the Asalon 4 EmailTop campaign. It is then up to the GM and players to interperet the skills. I'd rather not have specific rules about what a specific skill can and can't do - my approach would generally be very permissive and rely a lot on the character's background. In the given example, we have two characters: Conan the Barbarian, who does nothing but go monster hacking with his sword, and Prince Andrew, who is an educated master swordsman. I'd allow Andrew to use his Melee(Sword) skill to glean some information about a specific sword (assuming he didn't have a more relevant skill) but not Conan. As I said though, it's up to the individual GM.)

personally, I prefer fewer, more broadly applicable skills (see
UnknownArmies?, Sorcerer?) (Some skills are core - I'll explain this in the Skills chapter which has yet to be typed up. But basically this means some skills can't change, for example Toughness and Defence. This means that a given campaign's skill set must include these. But then to mimic a UA-style skill selection, don't have any other skills. Let the players come up with their own skills, which can be as broad or narrow as you like. My belief is that picking skills from a longish list is simpler than coming up with your own skills, and the overiding goal is to keep things simple.)

can you buy more specialised skills? (Currently you can simple make a more specialised skill but you won't receive any particular bonus for doing so - e.g. Tinker vs. Warp Drive Engine Fixing. I don't know if there's a simple way to do this - suggestions welcome.)

improvement/XP: how about just keeping track of XP and deriving
max rank, max special rank and number of specialised skills (XP div 6, XP div 4, XP div 16), and simply being able to buy ability increases &
skill ranks (Because I want to avoid the situation where a character only buys ranks in one skill and pushes up the relevant ability score otherwise. One could argue that this is a valid character choice - the ultra-ultra specialist - but it doesn't make for interesting roleplaying. The current advancement system requires that a character advance in at least 9 different skills. A specialist type character could always choose those skills closely related to his specialty: e.g. combat focused characters choose Melee/Ranged (weapon of choice + 2nd weapon), Brawl, Defence, Toughness, Reactions, Concentration, Spot, Listen.)

numerological scrutiny suggests cool things should also derive from XP div 36

magic: hoo boy (not relevant to this campaign though, thank goodness)

other suggestions came to mind, but would move away from "simple d20"
to "not d20 at all really" or "why don't you use system X?"