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Organized Combat System (OCS)

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Organized Combat System (OCS)

Post Number:#1  Postby The Keeper » 25 Apr 2010, 11:12

OK. Most of my friends are familiar with this game. The first incarnation was simply called Survival and occupied about 3 hand-written notebook pages.

Survival was all about surviving the impossible battlefield scenario. The game is simply a shoot-em-up. Characters are rolled in lots as a set of statistics and there is pretty much zero character development (no XP system was devised). You are issued a gun, ammo, some grenades, maybe a backup weapon or so and sent out to attack something. If your character dies you simply go on with the next set of stats you rolled up. The new character picks up. Supposedly by the time you run out of pre-rolled characters the objective is achieved. You then move on.

However, I've had some intense situations where we have had to do more rolling of stats. That was fun. The system is universal. Originally the situation was intended to be a Russian-USA conflict (this was written in 1986) but any conflict will serve. I have used it for space-fantasy combat scenarios.

Around 1989 I revised it. Again, hand-written, but more pages this time. I called it the MCS (Military Combat System). This re-write was intended to make it more universal across time genres. How to explain M-16s in a future war? For those wondering, no, I did not intend for either the MCS or Survival to allow for combat in any time period before the Cold War. It can certainly be modified for that though if you want to make your own rules. In redoing this though I created a whole bunch of new rules that took the spirit of the game out of it. So, I never really used the MCS, but stuck with Survival.

Eventually, I started on a third re-write. My intent this time was to create an easy universal combat system that combined guns and magic and energy weapons, or covered about anything you can think of. I have not completed the re-write. However, I am posting below what I have, so if you want to use what I have - go ahead. I call it the Organized Combat System (OCS). Kind of funny considering that the first version (Survival) is highly UN-organized.

You can use the OCS for any time period, any setting and any kind of technology. It covers all of that by using a simple power classification (as you will see).

Hopefully you will find it useful. In the future I will probably post up the other two versions, probably Survival first. Anyway, here is the OCS:


The Organized Combat System (OCS) is a complete game system, easily modifiable to fit any scenario or world. OCS is geared for quick character-generation and quick combat-resolution. Realism was not considered a component in the design of the game. Playability and fast-pace is the focus. To completely enjoy the experience of OCS, it should be played un-modified. However, the GM is of course free to modify the system in any way he sees fit.


This is the third edition of this game. The 1st edition was known as Survival, and had a completely military slant. This is still the unofficial name of this game. The 2nd edtion was the MCS, or Military Combat System, also with a completely military slant.
The first edition was a rules system generated on the fly. It made no differentiation between man, or object. Consequently, it made for a lot of heroic (or improbable) accomplishments for both PC and NPCs. It's arbitrary military ranking system also made for far-out situations. The second edition moved to correct these two problems without sacraficing any of the first editions playability. This was done simply by a restructuring of some dice rolls and a rank cap put on the rank generator. The rank generator was also listed as optional, which allowed the system for the first time to be used to generate characters for other military oriented scenarios. The second edition still contained its military slant, however.
The 3rd edition (OCS) is different. It contains much of the same rules as the previous editions, but can now be used for a variety of different worlds, scenarios, or situations. These rules are now referred to as the Core Rules. Playability has not been sacraficed at any time for realism.


The format of Survival is quite different than previous editions. Each section has now been numbered and referenced and rules can easily be found. Charts are better organized, but contain the simplicity of previous editions.


OCS uses the following dice: d4, d6, d8, d10, d12, d20, & d30.
Rule of High/Low: Any natural roll of 1 automatically fails.
Any natural roll of the die's highest number automatically succeeds.



Physical Capacity (PC) - capacity for physical exertion and endurance.
Mental Capacity (MC) - capacity for mental exhertion and endurance
Averaged Capacity (AC) - capacity averaged from PC & MC (round down)
Hits - capacity to withstand an attack (mental and physical).


Type 1: d4 for stats.
Type 2: d6 for stats.
Type 3: d8 for stats.
Type 4: d10 for stats.
Type 5: d12 for stats.
Type 6: d20 for stats.
Type 7: d30 for stats.
Type 8: 2d10(%) for stats.
Type 9: Variable* for stats.
Type 10: GM Defined** for stats

Common Men are Type 6. All other beings are of an appropriate life type as determined by the Game Master. In general however, Life Types 1-5 should be used for beings weaker than Common Men, while Life Types 7-9 should be used for beings that are stronger. Type 10 is reserved for beings of extreme strength or toughness (gods, spirits, etc...)
* Variable means any dice the GM wishes to use for this life type.
** GM Defined means the GM chooses his own stat numbers.

2.1.2 HITS+

Type 1: - d4
Type 2: - d6
Type 3: - d8
Type 4: - d10
Type 5: - d12
Type 6: 1-4 d4
5-6 d6
7-8 d8
9-10 d10
11-12 d12
13-20 d20
Type 7: - d30
Type 8: - 2d10(%)
Type 9: - Variable*
Type 10 - GM Defined **

+ There are no PLAYER re-rolls for stats/hits.

Roll for both mental and physical hits.


Choose a class and or/profession for the character. The GM has final approval of all class/professions. Characters may be dual or multi-class/profession. CLASS/PROFESSION - RESTRICTIONS [OPTIONAL]

If section 2.1.3 is being used then the following restrictions apply.
Characters may become dual or multi-C/P. Simply add the next C/P at the next level of progression. Single and dual C/P characters may not switch their C/Ps. They must become multi-C/P in order to gain that benefit. Multi-C/Ps may only change their third C/P and only at the next level of progression. Any abandoned C/Ps will freeze at that level of progression. Further progression in that C/P is not possible.
It is recommended that the Game Master apply this rule to prevent superhuman or totally out-there characters, but the GM is left to his own discretion.


It is suggested that for realism all characters start with a grade1 rank. However, if the GM and players must have a random system, see below. Ranks are listed as grades 1-5, alongside the rankings from the MCS. Game Masters must determine the title and responsibilitys of each grade if the MCS rankings do not apply to the situation at hand.

1-2 Grade 1 / Private
3-4 Grade 2 / Corporal
5-6 Grade 3 / Sergeant
7-8 Grade 4 / Lieutenant
9-10 Grade 5 / Captain

If the MCS rankings are used then the following definitions of those ranks will apply. Privates, are the lowest-ranking enlisted men. Corporals, are the lowest-ranking non-commissioned officers; in MCS/OCS they typically command two privates, making a three-man team [Team]. Sergeants, are the highest-ranking non-commissioned officers; in MCS/OCS they typically command a seven man team of four privates and two corporals [Squad]. Lieutenants, are the lowest-ranking commissioned officers; in MCS/OCS they typically command a fifteen man team of eight privates, four corporals, and two sergeants [Platoon]. Captains, are the highest-ranking commissioned officer allowed to remain in the field (except in special cases); in MCS/OCS they typically command a forty-six man team of twenty-four privates, twelve corporals, six sergeants, and three lieutenants [Company].


It is assumed that character class/profession selection will endow the character with the necessary knowledge to perform the abilities of his class/profession. These are known as the character's abilitys. The character has one for each C/P he possesses If the Game Master wishes to expand on this base, then see the optional rules below.


It is not the intent of this game to create a long and elaborate list of complicated skills to be used with intricate table and charts. This section is entirely optional, but all attempts have been made to keep it simple if used.
A character gets one ability (as mentioned above) per C/P. The character has a +1/level of progression in that ability to any die roll made against it. Thus, a fifth level Fighter has a Fighter +5 ability. In regards to the basic game, this rule is generally all that is needed. The GM may apply it as he sees fit.
Skills refer to areas of specific expertise. A character's MC determines how many of these skills he may have and is the number of 'points' he may divide into all of them. At each level of progression the character may perform this process again. Each point equals a +1 to any skill roll for the skill in question.
Players may choose any skill from any game for their character that they desire, or they may create it. However, as noted above, skills are specific and any skill selected for a character must reflect that. There are no Heavy Weapon skills, although there may be a .50 caliber machine-gun skill.


Game Masters that wish to use spells, psionics, or dietys in their scenarions can use the following options.
This section operates much like section 2.1.6. A character's MC determines either how many spells, powers, or favors a character has and how many Spell Points (SP), Power Points (PP(for Psionics)), or God Points (GP) he may divide into them. At each level of progression the character may perform this process again. Each point equals a +1 to any roll for the spell, power, or favor in question.
Players may choose any spell, power, or favor (or spell) from any game for their character that they desire, or they may create it. Spells, powers, and favors should be specific and descriptive in nature.
A second option is to have the player state the effect he is trying to achieve. The player may then assign a number of points equal to his MC to power the effect. This option is more versatile, but the GM should be careful not to allow the players too much leeway.
It is strongly suggested that unless the optional rule is being used, characters not be allowed to have all three powers in this section. A spell-casting, psionic, divinely-favored being would just ruin everything in sight.
If using optional rule, then the player must decide which two powers he wishes his character to have. No character may have both spell-casting, and psionic powers, unless a Type 7 or better, or at the GM's discretion.
Overpower Players may elect to overpower (that is attempt to use more power than they have) a power when a roll is called. This will result in the following effects. For every point of overpower the character must make an MC check at +1. The result must be under, but not equal to the MC or the character suffers a loss of MC equal to the amount of overpower. If the character has a 1 in MC he cannot attempt to overpower. There is a real risk in overpowering a power and unless you have the points, this is not suggested as it can ruin your entire day. The effects can be read as either spell-burnout, power loss, or divine retribution for being impertinent.




Grade 1: d4
Grade 2: d6
Grade 3: d8
Grade 4: d10
Grade 5: d12
Grade 6: d20
Grade 7: d30
Grade 8: 2d10(%)
Grade 9: Variable
Grade 10: GM Defined

The GM should select the difficulty level for the roll and then roll the appropriate die, adding in any applicable modifiers. He should then tell the player the appropriate stat (MC, PC, or AC) to use for the player's die roll. The player gets a die according to the table in section 2.1.2. If the player's die roll is equal to or greater then the difficulty roll then the player has succeeded. If not, the player has failed.


This is a skill check against a target that is either unwilling or uncooperative. The character gets the appropriate die from his PC, MC, or AC adds in any skill modifiers and rolls against the appropriate stat of the target. Beating the target's roll means success. A tie, or less is failure.
The target gets his stat die, plus any modifiers for cover, skill, etc.


In a stat check, the player must simply roll under the appropriate stat with the appropriate die (see section 2.1.2) and any applicable modifiers. A roll that is equal to the stat or above fails.



I. Iniative
II. Attack/Defend
III. Damage


Roll 1d6 and add to AC or Agility (AG). Highest roll wins the initiative and a tie means simultaneous combat with no damage applying until the end of the round.


Roll the appropriate die, add all appropriate modifiers for skills/powers and add to AC or Attack Ability (AA). Opponent does the same, but adds to either AC or AG. If the attacker's die roll is higher he has hit. If the defender's die roll is higher, the defender has been missed. All ties go to the defender. MODIFIERS TO ATTACK/DEFEND


Grade 1: d4
Grade 2: d6
Grade 3: d8
Grade 4: d10
Grade 5: d12
Grade 6: d20
Grade 7: d30
Grade 8: 2d10(%)
Grade 9: Variable
Grade 10: GM Defined

In OCS, a weapon is defined as any item used to attack or harm an opponent (or item). Shield/Cover is defined as any item used to protect something or someone from an attack. Each weapon/shield/cover is defined loosely by grade. The attacker gets the DIE type, according to the above chart to add to the attack roll. The DEFENDER recieves a die as well in his defense roll, according to the chart indicated by the type of shield, or cover he may have. Note, that while it is possible for the defender to have both a shield and cover, the defender will receieve only the HIGHEST Grade die (his shield and cover are NOT cumulative).
As mentioned above, these grade definitions are loose, so conventional definitions of these terms are NOT ALWAYS APPLICABLE. SKILLS/POWERS IN COMBAT

Certain powers or skills may be "ATTACK ORIENTED". The GM has two options in their treatment.
If the skill/power is obviously a modifier to the ATTACK ROLL, add the modier to that roll and treat as normal. If however, the skill/power is not a modifier, then it is a WEAPON and should be resolved according to table (GM sets the grade). EXCEPTIONS TO THE RULE

OCS has a limited number of exceptions to the rules. There are certain weapon types that do not fall on the chart, most notably grenedes. Please see below.


Mass Weapons are defined as weapons that deliver large amounts of damage. Naval weapons, nukes, or Mass Death spells are some of these. The difference with these weapons is that they AUTOMATICALLY KILL. The only results to be determined is HOW MANY. Use Table to determine the grade of mass weapon and thus the die to roll for NUMBER OF PEOPLE KILLED OR THINGS DESTROYED. The GM, at his discretion may wish to use the same table to determine a grade of COLLATERAL damage and roll the corresponding die for number of Hits taken. Other than the Defense roll, there is no save against this kind of damage. A HIT with a mass weapon does not necessarily indicate a DIRECT hit. It does mean, the weapon does its intended damage to the target.
Characters that miss with a grenede or mass weapon due to the defender(s) better roll MUST roll a DEFENSE ROLL against their own ATTACK ROLL. This is to see if the grenede has bounced back, the mass weapon blew up, etcetera. Any character failing to make this roll dies - NO EXCEPTIONS! The GM may also determine by circumstance if the character takes collateral damage, but only if the character has made his defense roll.
These rules assume shrapnel grenedes or mass weapons that kill. Flash, concussion grenedes (or other types), or mass weapons that do damage other than outright killing will assume not number of people killed, but blinded, knocked out, etcetera, AS IS APPROPRIATE FOR THE WEAPON BEING USED.
Also, there are mass weapons whose damage is indicated in tens, hundreds, thousands, or more of people/things affected. The GM should determine this and let the result stand in that number.
Game Balance To prevent every character from using only mass weapons within the game, it is assumed that these weapons are either not commonly available, or not easily usuable. Also, the rules above show the danger of missing your intended target. RANGE

OCS does not normally deal with range modifier as combat is normally closed. However, in the event that range should logically apply, the following should be considered. Each weapon has four range grades. The represent Closed, Short, Medium, and Long ranges. See the table below for the modifiers.


Closed: 0
Short: -1
Medium: -2
Long: -3

In OCS no weapon will do any damage past long range. Higher grade weapons will obviously do better at higher ranges. The GM should make these ranges appropriate to the weapon grade. It may be possible for a starship to do orbital bombardment several light years away at long range, but no character (generally) should be able to throw a knife that far.

4.1.3 DAMAGE

Once the Attack/Defense roll has been resolved and it is determined that there is a hit, damage applies. Roll the die indicated by table to determine the amount of hits taken by the defender. If the defender is left with one hit, he is unconscious. If zero, or less the CHARACTER IS DEAD - NO EXCEPTIONS! Characters starting with only 1 hit are assumed to be conscious, and are the only exception to the 1 Hit/Unconscious rule.
Since Hits is a general trait, it is possible to be killed by mental damage.
Players suffering damage receive a -1 per hit missing from their total Hits to all rolls.


Characters wearing armor or items with armor will take any damage to their Armor Value (AV) first, and then to Hits. Vehicles, and the like do not have hits, but only an AV. Breach this and the item is incapacitated. Armor degrades, and will not heal unless repaired.
In the case of Mass Weapons or Grenedes, AV is a modifier to the characters defense roll (+1 for each point of AV).
Armor is loosely defined. It may be magical, or real depending on the game situation.

4.1.4 END

After damage is resolved, determine the following. Are both opponents still standing? If they are, do they wish to continue fighting? If so, then repeat the entire process until either one or both opponents can no longer fight, or wish to withdraw. WITHDRAWING will give the attacker, one free attack. Since the defender is withdrawing, he receives only an unmodified defense roll (but gets cover mods).
If the defender has succeeded in his defense roll, he does not take damage and escapes. The attacker must go after him if he wishes to continue the fight. If the defender fails the defense roll, he takes damage and will be subject to free attacks unless he either decides to fight again, is incapacitated, or manages to break away.
Attackers wishing to pursue fleeing characters should make a PC roll against the defender's PC. A successful roll means combat is again joined with the attacker making the first attack. If the defender is successful, he escapes.
Note that the combat situation, certain powers/skills/items, etc. may prevent ANYONE from withdrawing. Defending characters should be extremely aware that it is DANGEROUS to withdraw from the field, unless they have the advantage.

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