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General Game Rules for the Atomic RPG System

The Game Master, also known as the GM, will be responsible for running the Atomic Role Play Game. The Atomic RPG System has been simplified for quick and easy game play. Here are some Atomic RPG System game rules to help make decisions on what a character can do or if they will be successful.

Since the Atomic RPG System System is so open and inviting to an almost infinite amount of play styles and games, it will be impossible to cover every situation. However, these additional rules may help keep your Atomic RPG System game running smoothly. If questions remain about how to work through a certain situation or setting, please feel free to post in the Atomic RPG System Forums.

Most of the Atomic RPG System game rules will be explained in other specific sections. However, situations that don’t quite fit or are GM-specific and not player character-specific may be mentioned here.

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GM Bonuses and Penalties

There are many times during a Atomic RPG System game where the GM needs to assign an additional bonus or penalty to a situational roll. The Atomic RPG System makes this process very fast and easy for the GM. GMs in the Atomic RPG System simply say if the temporary GM bonus or penalty is Minor, Major or Superior.

This will be a one-time modification to whatever the player is rolling. The player will use the characters Character Tier as a base and multiple it but the severity of the modification.

This method can be used in just about any situation the character rolls a d20, though it should used sparingly as the Atomic RPG System as a whole takes most things into account. This way the GM and the player do not need to agonize over what a modifier should be.

This is considered a GM Modifier specifically, so it will stack with everything.

Minor

x1 Character Tier
This would be a small bonus or penalty.

A character that is from the town they are searching might get a Minor bonus on their check.
A character that has just insulted everyone in the room is going to get a Minor penalty to Parley.

Example: A 9th level character (Character Tier 3) would have an additional 3 modifier. ( Minor x CT = 3 )

Major

x2 Character Their
This would be a medium bonus or penalty.

A character that is the child of the mayor of the town they are in might get a Major bonus on their check.
A character that has just destroyed all the art in the room is going to get a Major penalty to Parley from the art dealer.

Example: A 9th level character (Character Tier 3) would have an additional 6 modifier. ( Major x CT = 6 )

Defense

x5 Character Tier
This would be an extreme bonus or penalty.

A character that part of the royal line of the country might get a Superior bonus on their check to get aid.
A character that has just destroyed all the art in the room and previously robbed the place, is going to get a Major penalty to Parley from the art dealer.

Example: A 9th level character (Character Tier 3) would have an additional 15 modifier. ( Superior x CT = 15 )

What Stacks with What?

When calculating all character statistics and numbers there is one important rule to remember:

No character bonuses of the same type stack.

The lone exception to this rule is a GM bonus to anything. The GM always has the ability to grant bonuses (or penalties) that will stack with everything else a character may have. Character Bonuses and Character Penalties are treated as separate types. Characters will always use the greater bonus when deciding between bonuses of the same named type. If a character currently has multiple bonuses of the same type and for some reason the character loses the greater bonus, the lesser bonus will immediately take effect. In other words, player characters can have many effects of the same type active but only one gives them a bonus at a time.

Here is a list of the base bonus types used in the Atomic RPG System system:

  • Base Score: The score your character starts with is not a bonus.
  • Specialty Bonus: A bonus from a Specialty.
  • Item Bonus: A bonus granted by wearing an item.
  • Item Penalty: A penalty imposed by wearing an item.
  • Power Bonus: A bonus from being effected by a Power.
  • Power Penalty:  A penalty from an enemy’s Power.
  • Combat Bonus: Any bonus gained from your combat prowess such as when flanking.
  • Environmental Bonus:  A bonus OR penalty due to the environmental conditions (such as a blizzard).
  • GM Bonus: Any bonus granted by the Game Master.
  • GM Penalty: Any penalty imposed by the Game Master.

 

Knowing the way these bonuses and penalties work together will speed up the Atomic RPG System game. Most of these are automatically calculated on the Character Sheet. The few that are not are situationally based which are easily added into the rolls for the situation.

One thing that  can confuse characters is does Damage Dice or Healing Dice stack? The answer is YES! Meaning you can stack 3d5 damage over 3 Rounds with 2d4 Damage over 2 Rounds. All that Damage would be counted. Though you cannot stack Damage bonus, such as +2 Damage and +4 Damage. Only +4 Damage will work. The same concept is true for Healing. 

Environmental Effects

Environmental Effects are a very easy game rule that GM’s can use in many situations.

They can be used when a there is a mild storm.

They can also be used when players are out of their element, such as stuck out at sea. Environmental Effects also come into play when the players are in a deadly environment, such as being sucked out of an airlock into space!

This makes it much easier to implement, manage, and create the wacky situations players may find themselves in.

There are three distinct levels of Environmental Effects to use in the Atomic RPG System. Here they are and the game rules that will need to be applied to each. 

This affects Attack Rolls, Skill Checks, and Combat Maneuvers.

CT is Character Tier.

Minor

CT Penalty to d20 Rolls.

This will be used most of the time as the default Environmental Effect.

Use as a game rule when the players are having a harder time than normal in the environment.

Perfect to use in situations such as being in a storm, during dusk or a moonlit night, or even when the person is sick.

Major

CT x 2 Penalty to d20 Rolls.

Speed is reduced by 2.
This is used when the players find themselves in a place or situation that is completely foreign to them.

Major Environmental Effect is a good game rule to apply to situations such as doing things in a pitch black night, or stuck afloat at sea, or even when they are bedridden with a nasty case of the plague.

This represents the difficult challenges to the player in working in an very foreign situation.

Deadly

CT x 5 Penalty to d20 Rolls.

Speed is reduced by CT +2.

Lose 25% of total maximum HP every round.
Deadly Environmental Effect will occur when the players find themselves in a deadly place or situation. It is a great game rule to apply to situations such as in space without a spacesuit, falling into lava in a volcano, or stuck in the deep ocean unprotected. This should only be used in rare situations.

If the Deadly Environmental Effect seems extreme, it is! It should only be used in rare situations. The players need to be aware of the Deadly Environmental Effects. The amount of damage continues to increase past 100% because Recovery, Resistance, Powers, and other things may come into play.

Smart groups of players will work together to grant bonuses and heal players that enter areas with Deadly Environment Effects.

Here is an Environmental Effects chart to help classify a situation. This is not a hard and fast rule, just a tool a GM can use to set the Environmental Effects. This is designed so that “Normal” is average human conditions. For each of these 4 basic areas that are off “normal”, one step of Environmental Effects can be added. Note, these steps should be considered extremes. So “Hot” is not just a warm day, but a record-setting day. Scorching is literally scorching: easily flammable items can and will spontaneously combust. Dark is not a dark starry night–it is absolute darkness.

Environmental Effects Reference Table
LightDarkDimNormalBrightBrilliant
TemperatureFrigidColdNormalHotScorching
AreaSolidLiquidNormalGaseousVacuum
WaterSoakedWetNormalDryBarron

When comparing Environmental Effects between PCs and NPCs, take into account the “Normal” for the NPC. For example, if the player characters are in the arctic and encounter a polar bear, the player characters will consider the temperature is cold, but everything else is Normal, so they will be dealing with a Minor Environmental Effect. For the polar bear NPC, everything is Normal, so it will not suffer any Environmental Effects.

Underwater Environmental Effects

One of the most common Environmental Effects the party is likely to encounter is water. Just swimming on water is fine, but what happens when the character is submerged underwater? The solution is easy. The player will have Minor Environmental Effects while it can hold it’s breath. As soon as it can’t the character starts to drown. At that time the player will be affected by Deadly Environmental Effects because they are dying! See the Athletics Skill or Nature Skill to see how long players can hold their breath.

Movement Modifiers and Difficult Terrain

Movement Modifiers are used by the GM to make certain terrain or areas difficult to move through. These give the GM the ability to modify the battlefield in interesting and challenging ways. This can greatly enhance combat and strategic battle.

Minor Movement Penalty

Each Space counts as 2 Spaces for Movement.

Examples include terrain like a few inches of mud, ice, or spider webs.

Major Movement Penalty

Each Space counts as 3 Spaces for movement.

Examples include terrain like deep mud, snow, or swamp.

Battle Surprise - Spice up Battle Time

These are unexpected things that can happen during Battle Time that can make combat much more exciting. 

The GM should look at the below list of ideas and manually add them to appropriate Encounters on occasion.

If nothing sticks out the GM can roll in secret on the 2nd or 3rd round of the Encounter if they want to inject a random Battle Surprise.

Read more about Battle Surprises on this blog post: Battle Surprise Blog Post for Battle Time

Random Battle Surprise

d20DescriptionEffect
1A terrible storm or other weather like phenomenon occurs. If indoors there is a sudden gas leak, pipeline break, or power outage.Major Environmental Effect
2Damage Hazard – Fire pit, acid pool, or other damaging area is discovered or appears.d20 x Character Tier Hit Point Damage
3Movement Obstacle – A tree falls, a pit is discovered, or security doors drop to change the battlefield.25 Spaces – DC 40 Bypass
4Movement Hazard – Area on battlefield becomes difficult to move in or through. Oil, blood, rubble or debris restrict movement.6×6 Area – Spaces Count as 3 when moving.
5Reinforcements ArriveA few more of the weakest NPCs arrive to bolster the ranks.
6Movement Hazard – Area on battlefield becomes difficult to move in or through. Oil, blood, rubble or debris restrict movement.5×5 Area – Spaces Count as 2 when moving.
7A storm or other weather like phenomenon occurs.Minor Environmental Effect
8Movement Hazard – Area on battlefield becomes difficult to move in or through. Oil, blood, rubble or debris restrict movement.4×4 Area – Spaces Count as 2 when moving.
9Movement Obstacle – A tree falls, a pit is discovered, or security doors drop to change the battlefield.16 Spaces Area – DC 30 Bypass
10Damage Hazard – Fire pit, acid pool, or other damaging area is discovered or appears.d10 x Character Tier Hit Point Damage
11Movement Hazard – Area on battlefield becomes difficult to move in or through. Oil, blood, rubble or debris restrict movement.3×3 Area – Spaces Count as 2 when moving.
12Movement Obstacle – A tree falls, a pit is discovered, or security doors drop to change the battlefield.9 Spaces Area – DC 20 Bypass
13Damage Hazard – Fire pit, acid pool, or other damaging area is discovered or appears.d6 x Character Tier Hit Point Damage
14No Battle Surprise – Just go about the Battle Time Encounter as normal. 
15No Battle Surprise – Just go about the Battle Time Encounter as normal. 
16No Battle Surprise – Just go about the Battle Time Encounter as normal. 
17No Battle Surprise – Just go about the Battle Time Encounter as normal. 
18No Battle Surprise – Just go about the Battle Time Encounter as normal. 
19Enemies flee or surrender.Enemies surrender or flee at 25% Hit Points.
20Enemies try to kill other enemies to gain station or repay a grudge. They include them in attacks or at the least fail to help them in the most advantageous way.Enemies attack enemies.

Availability of Items to Characters

Sometimes it can be difficulty to determine how common items might be or how easily a PC is able to get a hold of something they are seeking.

Often times the GM has a good idea depending on their campaign setting. However, it might be a good idea to use the table below to get an idea of the general availability of items in the Atomic RPG System

Here is a quick reference table Atomic RPG System players can use to get a general idea if an item is available. Remember, it is always ultimately up to the GM, this is just a guideline.

AvailabilityDescriptionCostRoll
CommonCommon items that just about anyone has. Common items are easy to find.4,0005 or Higher
UncommonThis is an uncommon item which may be expensive or hard to come by.10,00010 or Higher
RareThis item may be available but expensive and hard to come by.26,00015 or Higher
Very RareThis item is rarely available for purchase. Usually a substantial sum of cash is needed as well as some kind of service.68,00018 or Higher
Unheard OfThis item is never available for purchase. If someone is lucky enough to have such a powerful item they never give it up voluntarily.178,00020
  • Availability – The name used to describe how available the item is.
  • Description – A quick description on the item’s availability.
  • Cost – The base cost of this level of availability. No matter what the item is, its value will determine its availability.
  • Roll – The roll that would be needed if the player is allowed to even make a roll to see if the item is available for purchase or trade. Rolls are made with a d20 (20 Sided Die). The player can add their Character Tier to the roll.

 

These are the Atomic RPG System Game rules that do not fit well in other sections of the Atomic RPG System website. Most rules for the Atomic RPG System are explained in full in the specific section of the Atomic RPG System website. Use the search feature on the Atomic RPG System website to find the game rules you are looking for. For further discussion and clarification on specific Atomic RPG System game rules, look on our Atomic RPG System Forum or Atomic RPG System FAQ page.

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