AS PROMISED BELOW FIND THE COMBAT SYSTEM THUS FAR.
Damage Types
Blunt- a type of damage that deals bludgeoning damage like punches or kicks.
Lethal- a type of damage that can cause fatal harm like weapons, lightning, arrows, wind blades, etc.
Aggravated- A severe damage type caused by certain techniques that is hard to heal and immensely deadly and or debilitating, fire jutsu, kinjutsu suicide techniques, massive explosions and the like.
Health levels roll over if you have 8 health levels and are dealt 8 blunt damage you are unconscious but any more blunt damage becomes lethal damage if your health box fills with lethal or aggravated you are dying or dead.
Lethal is not immediately fatal if health is filled with lethal that lethal will advance to aggravated 1 health level every ten seconds until you are treated or dead.
Aggravated damage if full is immediate death and represents advanced body destruction like heavy burning, shrapnel peppering, or massive organ failures.
Blunt hits to the head and throat if they deal 6 or more damage over soak and armor are treated as lethal instead of blunt. Getting your skull caved in is very much a lethal injury.
Combat Stages
Combat has 2 stages hitting and damage hitting is dexterity plus a skill typically brawl or weaponry. Damage is strength plus the weapons damage rating or martial arts skill. Hitting is difficult read below.
Hitting is measured against defense a combination of athletics and dexterity.
If hit is higher than these the attack hits and damage is dealt.
Damage for thrown or hand powered weaponry is strength plus the weapons rating a kunai has a weapon rating of 1 and if wielded by strength 5 ninja potential damage is 6 lethal.
Damage for non-assisted weapons like bows or senbon launchers is static only the weapon damage is dealt if a bow does 4 lethal high strength will not change draw weight. critical hits and hit bonuses can though.
The successes in the hitting stage add to the damage stage up to a maximum of 5 to show a well-executed attack against a clearly inferior opponent. A master swordsman strikes truer.
So dex 5 wep 5 against defense 4 bandit 10 - 4 = 6 -1 successes since maximum is 5. Kunai hits damage is strength 5 plus kunai 1 = 6 plus 5 successes =11 lethal damage dealt and likely a dead bandit.
After an attack hits soak is automatically used let's say that bandit had steel lamellar armor giving an armor of 6 against lethal and blunt damage. 6-11 = 5 lethal damage dealt still ouch.
Armor kept that bandit alive, but the damage dealt is still life threatening since the shinobi was skilled enough while attacking to target weak points in the armor. One more hit will likely kill.
A bow does 4 lethal but fired by someone with 6 dex and 6 weapons it has a hit of 12 against the same bandit 4-12=8 successes 8-3=5 usable successes 4+5=9-6= 3 Lethal damage dealt.
Critical hits and Ripostes
Critical hits sacrifice your hit carry over and half your hit chance 12 hit becomes 6. but it they hit deal triple damage and ignore non-jutsu armor. so that 4 lethal bow does 12 lethal on crit.
Chakra armor strong enough to absorb the normal hit however will still stop a critical hit if it covers the whole body as critical hits are targeting weak points for max damage.
No weak point = no max damage.
Most skilled genin can crit bandits reliably most skilled chunin can crit genin reliably. Critical hits are deadly, but they are high risk. If your opponent has more defense than your critical to hit roll.
If an opponent has more defense than your attack has hit chance, they can choose to deal the difference to you in damage -1.
This is called a riposte this is doubly dangerous if a critical is failed.
Since a critical halves your hit chance a failed one means you will effectively take twice as much riposte damage such is the fate of those who underestimate their enemies.
Ranged attacks cannot be riposted unless the opponent has a ranged counter like kunai or specific jutsu. Wind for instance can riposte kunai and blow them back at an attacker if timed right.
The chakra defense bonus is focused on avoidance and cannot be used to influence a Riposte to achieve more damage. But it can be used to minimize the damage done by a riposte by moving away in a burst of speed. This requires twice the chakra expenditure and that you see the attack coming.
THROWN WEAPON RULES
Thrown weapons lose some damage potential in flight. You are typically better off stabbing an enemy with a kunai than throwing it. But certain jutsu's like elemental chakra coating can increase this lethality.
A Kunai does 1/4th strength rounded up, then plus 1 in damage if thrown.
A shuriken does 1/6th strength rounded up, plus 0 in damage if thrown.
A senbon is an inefficient weapon it deals 1/10 strength in damage rounded up plus 0.
All weapons when thrown can however add their successes from the hitting stage up to the maximum of 5 just like in melee, critical hits allow the full strength to be used so if you had 10 strength and hit with a senbon your normal damage would be 1 but a critical hits damage would be 10.
Example a solid Chunin level ninja 10 strength 10 stamina 10 dexterity 4 weaponry, throws a senbon at an average bandit 2 strength 2 stamina 2 dex 1 athletics, the bandit thus has a defense of 3 2 from dex and 1 from athletics.
The shinobi has a hit roll of 14 4 from weaponry 10 from dex the shinobi thus scores 11 successes on the hit roll. The maximum of 5 successes carries over as damage so 5 damage so far.
The shinobi had 10 strength but since the senbon is thrown it deals only 1 damage since its damage is 1/10 strength. 1 damage plus 5 damage from successes equals 6 damage the bandit had seven health 5 from size 2 from stamina, the bandit is severely wounded and nearly incapacitated he is crippled and suffers those penalties which are explained below.
Multi weapons in throws Shinobi are experts at throwing multiple ninja tools at once every additional weapon thrown lowers hit by 1 but damage is calculated normally for each weapon that hits. Mechanical weapon launchers and jutsu that multiply weapons ignore this penalty.
So, say our example shinobi throws six senbon instead of 1 their hit roll decreases by 5 so 14 is reduced to 9 that bandit still only has a defense of 3 so every senbon thrown will hit and deal six damage due to the hit still being 5 or more above the bandit's defense.
The bandit had 7 health but suffered 36 lethal damage the bandit is well and truly dead and the damage even looped around from lethal to aggravated killing them instantly. He has a senbon in each of his eyes, 1 in both temples and 2 through the corroded artery he collapses instantly.
DEFENSE RULES
Now let's cover the defense stat a bit and its rules.
Shinobi and chakra trained individuals always have their full defense in a turn even when they attack in a turn, they also can choose to defend by boosting defense with chakra expenditure as was covered in the chakra chapter.
Shinobi apply their full defense against up to 3 attackers in a turn after this it reduces by 2 for every additional attack, they defend against, shinobi are powerful but can be overwhelmed. Like the second Hokage was.
The exception being those with Sharingan, Rinnegan paths, or Byakugan they have double this attacker limit and suffer only minus 1 penalty per additional attackers dojutsu are hacks.
If a shinobi is surprised, they cannot use their defense for the first round if they are ambushed but aware they deploy half of their defense the first round.
Normal humans and the like apply their full defense even when they attack in a turn, but they cannot further raise their defense like shinobi
Normal humans apply their full defense against a single attacker in a turn it is reduced by 3 for every additional attack they defend against.
Temporary Effects of Damage on Attributes
Effects of damage.
Wounded damage in last 5 health levels -3 to physical attributes.
maimed damage in last 3 health levels -6 to physical attributes.
crippled damage in last 2 health levels -12 to physical attributes.
Attacks deal half damage if they hit arms or legs except for criticals.
An attack that deals 3/4 health in damage and targets a limb severs the limb or crushes it.
The legs have major blood vessels a well-placed kunai to the thigh can kill if it hits it. This is a critical hit for damage purposes.
SNEAKY THINGS
Not all shinobi fight fairly Naruto in part one springs to mind as an example.
In battle a shinobi may roll their sleight of hand and stealth skills vs an opponent's sleight of hand and inspection skills to launch an unexpected maneuver. This can be done any number of times but the difficulty of the roll goes up by 1 for every attempt as the opponent becomes more and more wary.
If successful on the next attack the opponents defense is halved. This allows inferior opponents a chance to harm higher level foes if they are crafty enough.
GRAPPLING
Grappling moves are Taijutsu maneuvers that rely on brute strength and technique more than dexterity.
Grappling is strength plus brawl versus an opponent's strength plus brawl. Like in melee combat additional successes over an opponent's roll add to the damage to the maximum of five.
GRAPPLING MANEUEVERS
Slam after succeeding the grapple roll use your strength and the opponent's weight against them to deal blunt damage. Damage is strength + successes + brawl + the opponent's size 1-6 for most typical human is size 5.
Choke after succeeding in the grapple choke your opponent to unconsciousness damage is strength+brawl in blunt damage every 5 seconds.
Takedown after succeeding in grapple sweep the leg to bring an opponent to the ground with you on top of them your next physical attack does 1 more damage and the opponent losses a quarter of their defense.
Disarm after succeeding in grapple wrench a weapon from an opponent's hands.
Armor rules
The ninja world has some forms of protection.
Jonin and Chunin flak vests grant 3 armor against all sources to the area they cover. Armor reduces damage by the flat amount listed if they hit the covered body part.
A 3-armor vest would thus negate 3 points of damage if the damage is above this the remaining damage is dealt.
Some Jutsu provide armor as well.
Soak is the human body's ability to absorb and better deal with blunt trauma think of a heavyweight boxer or skilled martial artist and how many hits some of them take as an example. Soak is equal to stamina x 2 and is a depletable resource in a fight. Soak only protects against Blunt Damage. Soak regenerates at 1 point per minute outside of combat.
Soak accounts for shinobi in the Naruto world apparently being fine after being slammed into cliff faces at Mach 1 Even though they can be killed by kunai and shuriken. Just assume people in the Naruto world always drink their milk I guess.
If I make any mistakes when writing and fail to follow these rules, feel free to call me out on it. I am endeavoring to make this gamer system easily understood and quantifiable to my readers.