Comparison: Calculating Melee Attacking Proficiency in different RPGs

Because I've recently been looking at other systems for inspiration to understand more clearly what GURPS does well and what it does not do well, I've decided to catalog a few side by side examples of combat from a few other popular systems. This post is trying to be objective as possible, with the caveat that I really like GURPS, so it is nigh impossible to be objective. The systems I have decided to compare, besides GURPS

• D&D 5E - Dungeons and Dragons is the anchor point for most people; that is, I feel like a lot of people will describe a system by saying how it does x better and y worse than D&D, so this is natural.
• Fate - An alternative generic role playing system that gives a great amount of narrative control to the players. Mechanics exist in favor of telling a good story and playing compelling characters.
• Savage Worlds - Another generic system, somewhat of an "in-between" for GURPS and Fate.
• Ryuutama - Just for giggles, a system that I've been learning that focuses on telling slice-of-life style fantasy stories rather than sword and sorcery battling and dungeon delving, but has a simple combat system nonetheless.

I hope this post is a (mostly) impartial, informative, and enlightening look at the complexities of various battle mechanics from several popular systems (and Ryuutama)

Determining Attacking Proficiency

First off, let's see what goes into determining a character's attacking proficiency. By attacking proficiency I mean what mechanics are used for determining how accurate and how damaging a melee attack can be.

GURPS

The Main Character

Starting off, of course, with GURPS, a melee attack's "accuracy" is determined by a skill level. A skill level is determined by the (relatively) expensive attribute dexterity (DX) and a "skill" for the type of weapon being used. For a broadsword, someone would use the Broadsword skill, for example. Most melee weapon skills have a difficulty of "average" with a few being "easy" or "hard", which determines how many points it costs to be proficient at using that weapon. The formula for calculating the cost for advancement in skills in GURPS 4th Edition is simple to memorize after playing a few games, and a table exists in both the free Lite edition, and the Basic Set. Namely, 1 level in a skill is 1 point, another level is an additional point, the next is two points, and after that, each level is 4 points.

Determining damage is a little bit trickier. Damage is based on a lookup table that correlates to the modestly priced Strength (ST) attribute. Damage from this formula gives two values a more modest thrust value, and a larger swing value; which is used depends on whether the weapon of choice relies on swings or thrusts; several weapons have both as options.

Most weapons will modify swing and/or thrust damage with an attribute saying something like, "sw+2 cut". If your Swing (sw) is 2d, then plugging that in like a pre-algebra problem, the weapon does "2d+2" damage. 

In summary:

• Proficiency equals DX + skill modifier
• Damage is calculated by finding a value on a lookup table by ST, and plugging it into a weapon's damage formula.

D&D 5e

In Dungeons and Dragons, the proficiency of a melee weapon is determined by the class you choose, and sometimes the race. The metric is literally called "proficiency" and proficiency increases by fixed amounts at certain levels. The player also uses a lookup table that is available in the free versions of the player's handbook that converts the Strength (STR) attribute into a modifier. This lookup table is probably more difficult than the GURPS skill table, but simpler than the thrust/swing lookup table, but nonetheless, simple enough to memorize after a few games. The STR modifier and the weapon proficiency make up the weapon proficiency in D&D.

Damage is associated heavily with the weapon used. Each weapon tells how many and what type of dice to roll. The STR modifier is also added to this. For example, a weapon that does "1d4" damage that belongs to a character with an STR modifier of +2 does "1d4+2" damage.

In summary:

• "Proficiency" equals Strength modifier found on a lookup table, plus proficiency modifier which is calculated by class and level.
• Damage is calculated by looking at the damage of the weapon on the weapon table, and adding the STR modifier calculated in the previous step.

Fate

Both proficiency and damage are determined by a skill level in "Fight" skill. Using "Fight" to "Attack" deals damage in the form of consequences to the opponent with a higher value allowing an attack to hit in the first place, and higher values dealing more severe consequences than lower values in the event that a hit is registered. Under certain situations, an "aspect" may be invoked to improve this value even further. I almost don't know if it is fair to include "aspects" here because it is similar to GURPS' advantages and disadvantages, or D&D's class features, but it seems so integral to Fate, it seemed important to include it.

In Summary:

• Proficiency is determined by the fight skill. Aspects can have a situational positive (or negative) modifer or allow it whatsoever.
• Consequences are resolved simultaneously with Proficiency so it is also directly related to the value of Fight skill and aspects.

Savage Worlds

Similar to Fate, there is only one "Fighting" "skill." This skill covers all weapons. Fighting is based on the "Strength" "trait". Levels in Fighting up to Strength are cheaper, and doubly expensive if greater than strength.

Damage is determined by Strength plus the damage attribute of the used weapon. If a fighter has a Strength of d8, and his weapon has a damage of d6, his damage is "d8+d6". Damage is dealt in terms of consequences, similar to Fate, but slightly different. A character is shaken by a decent amount of damage, and dealt a wound by a great amount of damage.

In summary:

• Proficiency is determined by Fighting skill alone; it is cheaper if the character has a lot of Strength
• Damage is determined by adding Strength and weapon damage attributes together.

Ryuutama

Fighting is a thing that naturally happens, but interestingly in Ryuutama, the strongest monsters in the entire bestiary give less experience than a single day of hiking in the rain.

Every character can be a "master" of one type of weapon, and some classes may be masters of two or more weapons. Any character may use any weapon, but injures themselves using a weapon that they have not mastered (!). Each weapon type has an associated formula for "Accuracy" and for "Damage" which is described as an equation using "Stats". Stats are raised at certain levels, and some weapons use some non-traditional stats for accuracy or damage. For example, a "light blade" has an accuracy of "Dex + Int + 1" and damage of "Int - 1".

In Summary:

• The formula for proficiency is determined by the weapon chosen. The attributes in the formula are determined by stat distribution.
• Likewise, the formula for damage is determined solely by the weapon chosen. Attributes are determined again by stat distribution.

Other Notes

At a glance, the mechanically simplest systems are either Ryuutama or Savage Worlds; GURPS and D&D are at the other end of the spectrum, and Fate is abstract to the point where it is hard to compare it directly, but it is also pretty simple and is close to the first two. I focused mainly on the calculations that need to be done usually only when stat progression occurs or when weapons are traded up. Mechanically speaking, granularity might be sorted from finest to coarsest starting with GURPS having skills for specific weapons, then D&D and Ryuutama having proficiencies or masteries for categories of weapons, and finally Savage Worlds and Fate for having one umbrella Fight/Fighting skill. 

When you compare them side by side, it is kind of interesting that in melee terms it seems like damage in GURPS is more determined by how strong the user is than how good his weapon is; whereas the inverse is true in D&D. Fate and Ryuutama, being systems that aren't predicated on combat have a more abstract formulation for damage; Fate doesn't objectively care what your favorite weapon or how many years of training you have; if your character is defined as fighting well, and circumstances are right, you fight great. Ryuutama has weapons that are good for tons of different stat distributions so your character doesn't have to feel useless in combat if you didn't make her Buffy McBeefCake.

If I continue writing entries in this vein, I hope to discuss the mechanics of calculating defensive proficiencies in a later entry, and the actual combat resolution in another.

Please! Correct me if any of this is wrong! I am pretty new to most systems besides GURPS, and any feedback and corrections for my own edification are appreciated!