Scratch:Basic Rules

The Scratch RPS provides simple rules for role-playing games (RPGs.) In an RPG, each player takes on the role of a character in a story or simulation. People play RPGs to have fun and socialize, but they can also be a fun way to practice basic math and problem-solving skills. A Scratch RPS character looks something like this:

Zimzambamalam (8 shooting, 2 toughness, 1 tgh/2, 11 defense) is a master of magic who destroys his enemies with bolts of lightning from his fingertips (using his shooting ability.) The mighty wizard relies on the awesome power of his magic rather than weapons or fancy footwork.

Each character has some abilities, and each of those abilities has a level. If a character does not have at least one level of an ability, the character does not have that ability and cannot use that ability.

Action

Some actions, like a character attacking another character, have a chance of success and a chance of failure. To determine whether the action succeeds, roll a twenty-sided die. (If you do not have a twenty-sided die, see the "Twenty-Sided Die Alternatives" section below.) Modifiers, such as ability levels, are then added to certain types of rolls. If the total is greater than or equal to the difficulty of the action, then the action succeeds. If the die roll is 20 before adding an ability level or other modifiers, then the action automatically succeeds. If the die roll is not 20 and the total is less than the difficulty, the action fails.

Ability rolls require a character to use specific abilities. If the character does not have the ability, they cannot succeed at the ability roll. The character's ability level is added as a modifier to the roll. "Make a command roll (difficulty 25)" or "beat a command roll of 25" means a player whose character has at least one level of command ability can roll a twenty-sided die then add his character's command ability level to the roll. The character is only successful if the total is equal to or greater than 25, or the player rolls a 20 before adding his character's command ability. For example, suppose a character with 3 levels of craftsmanship ability has to make a craftsmanship roll of 15. He rolls 12, and 12 plus 3 is equal to the difficulty 15, so he is barely successful.

Non-ability rolls are not affected by ability levels. "Make a non-ability roll (difficulty 11)" or "Make a non-ability roll of 11" means a player whose character is attempting the action should roll a twenty-sided die. The action succeeds when the roll 11 or greater and fails when the roll is 10 or less.

Characters have hit points which determine whether they are healthy, injured or incapacitated. Characters usually start combat with their maximum hit points. A character's toughness ability level is his maximum hit points. Tgh/2 is half of a character's toughness, rounded down. A healthy character has more hit points than his tgh/2. An injured character has at least one hit point but no more hit points than his tgh/2. Characters can never have less than zero hit points. A character with zero hit points is incapacitated and cannot perform actions.

For example, if a character has 7 toughness, his tgh/2 would be 3, so he would be healthy when his hit points are 4, 5, 6 or 7, injured when his hit points 1, 2 or 3, and incapacitated when his hit points are 0.

In combat characters take turns performing actions. Some attack actions cause damage when they are successful. Each point of damage reduces the target's hit points by 1. The difficulty of attacking a character is the character's defense, except when the rules specify a different difficulty. A character's defense is either 10 plus the level of his best defensive ability or 10 plus his tgh/2, whichever is greater.

For example, if a character has a defensive ability with 3 levels, and the character has 2 tgh/2, then his defense is 13 (10 plus his defensive ability, which is higher than his tgh/2.) If he is attacked and his attacker's roll plus applicable ability level is 13 (or more,) then the attack would be successful. (If the roll was 12 or less, the attack would fail.)

Most actions are regular actions. Characters can only perform one regular action per turn. They cannot perform regular actions when they are delayed, and they cannot perform actions while they are incapacitated. Characters can also perform one bonus action in addition to their regular action each turn. Bonus actions are actions which do not require the character's full attention, like opening a door, pushing a button or handing an item to another character.

Basic Actions

Every character can do some basic combat actions.

basic attack	A basic close range attack which causes 1 damage. If the attack is automatically successful, it causes 2 damage instead of 1. This attack requires a non-ability roll against the target's defense to succeed.
delay	A close range distraction or grappling attack delays the target until the end of the target's next turn if the attack is successful. If the attack is automatically successful, it also causes 1 damage. This attack requires a non-ability roll against the target's defense to succeed.
throw object	If a dangerous throwable object, such as a rock or chair is available, a character can throw it. This long range attack causes 1 damage if it is successful. If the attack is automatically successful, it causes 2 damage instead of 1. This attack requires a non-ability roll against the target's defense to succeed.
evade	Add the level of one movement ability to the character's defense until his next turn. A character without movement abilities can also evade, but his defense does not change.
catch	To catch an evading character, make a success roll. The difficulty of this action is 10 plus the evading character's movement ability. The catching character can add a movement ability to his roll. If the roll is successful, the evading character's defense returns to normal.
escape	A character can escape the battle if he evaded on his last turn and has not been caught or hit since that turn. The character cannot perform actions or be attacked for the rest of the fight.
engage	Before a regular close range attack action - like basic attack or delay - a character can engage his enemies as a bonus action. The attacker adds 2 to his close range attack rolls until the end of his current turn, but the attacker's defense is reduced by two until the beginning of his next turn. Lowering the attacker's defense may encourage enemies to target the attacker instead of his allies.
do nothing	A character can also do nothing instead of an action.

Abilities

Characters typically have between three and six abilities. All characters have toughness, most have at least one attack ability, and many have a defensive ability.

Characters may be created by distributing character points (CP) between 1 or more abilities. Each CP gives the character one ability level of that ability. No ability can receive more levels than a certain maximum level. The characters in the combat example which follows the list of abilities below were created with 10 CP and a maximum level of 4. These are good limits for making characters that are like average people. Chokestar was created by distributing 2 CP to piloting ability, 2 CP to toughness ability, 3 CP to wrestling ability and 3 CP to stalking ability, for a total of 10 ability levels, and no more than 4 levels of any single ability.

Here is an optional character sheet that can be used for the Scratch RPS: [| [Image:Preview.png|450px]]

Maximum level limit requires a character to divide his ability levels between a variety of abilities instead of putting all of his levels into a single ability. For example, in a game where characters are slightly more powerful than the average person, they might start with 12 CP and a maximum level limit of 5. Characters in this game would have to divide their CP between at least three abilities.

Appropriate abilities, CP and maximum levels for new characters depend on the setting and type of character being created. Scratch RPS abilities can be loosely interpreted or adapted to a wide variety of settings and types of characters. For example, shooting could be used with guns, bows, other ranged weapons or magic powers. See Scratch:Example Characters for more examples.

List of Abilities

Toughness is a character's maximum hit points, and represents armor, size or other damage-resisting traits. Most characters have at least 2 toughness. Characters who are big, physically fit, armored or highly motivated will have 3 or more toughness. Some characters might have only 1 toughness because they are particularly fragile or because they are unmotivated and give up as soon as they are injured. Characters without toughness may not perform actions in combat rounds

Shooting is used to perform an extra powerful attack against one character. If the attack is successful, it causes 2 damage. If the attack is automatically successful it causes 5 damage. If the attacker is injured, then using this ability makes him delayed until the end of his next turn.

Blasting is used to attack multiple opponents simultaneously with one big attack. Using blasting allows an attacker to attack three separate targets in one turn, but he cannot attack any single target more than once on that turn. Each successful attack causes 1 damage. Each automatically successful attack causes 2 damage instead of 1. If the attacker is injured, using blasting causes him to be delayed until the end of his next turn.

Knockout is used to perform extremely devastating attacks against a single character at close range. If the attacker is healthy, a knockout attack causes 4 damage. If the attacker is injured, a knockout attack causes 2 damage. If a knockout attack is automatically successful it causes 5 damage if the attacker is healthy or 3 damage if the attacker is injured. Using a knockout attack causes the attacker to skip his next turn.

Fighting is used to perform quick attacks against one or two enemies. If the attacker is healthy he can do two attacks on his turn. If the attacker is injured, then he can only do one attack per turn. Each successful fighting attack causes 1 damage. If a fighting attack is automatically successful, it causes 2 damage instead of 1.

Wrestling is used to perform delaying and damaging attacks. If the attacker using wrestling ability is healthy, he can do both an attack which delays an enemy until the end of his next turn and an attack which causes 1 damage on a single turn. If the attacker is injured he can only do one delaying attack or one damaging attack. If the damaging attack is automatically successful, it causes 2 damage instead of 1. If the delaying attack is automatically successful it causes 1 damage in addition to delaying the target.

Stalking is a defensive ability which determines the order of turns in combat. Characters with more stalking ability go first. If characters have the same stalking level, then randomly determine who goes first. (Roll a die for each tied character. Whoever rolls higher goes first. If they roll the same, re-roll.) When a player controls more than one character, all of those characters move and perform actions on the same turn. The highest stalking ability level of all the characters controlled by a player determines when the player's characters have their turn.

Acrobatics is a defensive ability and movement ability used to get up, across, or over three-dimensional structures and obstacles like ropes, nets, ledges, ladders, fences, trees and cliffs. Acrobatics can be used to catch characters who are trying to escape by using acrobatics, quickness and even flying when these three-dimensional structures are in the combat environment.

Quickness is a defensive ability and movement ability used to evade, escape and catch characters on relatively level ground. Quickness is used to catch characters using quickness or no ability to escape, but it can also be used to catch characters escaping with acrobatics, swimming or flying when the environment does not allow them to get far from solid ground (short trees, shallow water or low ceiling for example.)

Flying is a defensive ability and movement ability used to evade, escape, and catch characters who are escaping by flying and quickness. Flying can only be used where there is room to fly. (There is usually room to fly outdoors but not indoors.) When a flying character evades or uses a long range attack, he cannot be attacked with a close range attack until his next turn. Flying can also be used to catch characters escaping by climbing unless obstacles like tree branches protect climbers from fliers, and it can be used to catch characters escaping by swimming if the water is shallow. A character with no flying ability cannot fly, and cannot get flying ability unless there is a good explanation for why then can fly now when before they could not.

Swimming is a movement ability used to evade, escape and catch characters who are trying to escape in water. When a character is in water, add his swimming ability to his defense and close range attack rolls in addition to the ability levels normally added to defense and attack rolls. When there is deep water in the combat environment, characters escaping by swimming cannot be reached by characters who are flying, quickness or using acrobatics. A character without this ability does not know how to swim. Most land-dwelling species can only develop one or two levels of swimming ability without special equipment.

Healing allows a character to try to revive incapacitated characters and heal injured characters. A character cannot heal himself with this ability. The difficulty of reviving an incapacitated character is 10. The difficulty of healing an injured character is 10. After being successfully revived a character is still injured, and has only one hit point. After being successfully healed a character is barely healthy, with 1 hit point more than half of his maximum hit points (rounded down.)

Craftsmanship is an ability which allows a character to maintain and improve his allies' equipment. For each level of this ability, a character can give a traveling companion a temporary +1 bonus to an ability which is already at least level 1. He cannot give a second temporary bonus to an ability which has a temporary bonus from himself or someone else. The bonus lasts until he removes it or they are no longer traveling companions. He cannot remove or add bonuses in combat. He must make a success roll to add a temporary bonus in a hurry (usually difficulty 10.) If the roll fails he cannot use that temporary bonus until he is no longer in a hurry.

Command is an ability that provides a character with minions whose total ability level is no greater than the character's command ability level. None of these followers can have command ability or an ability level greater than half of the leader's command ability (rounded up.) A character with 4 command could have 4 minions with 1 ability level each, 2 minions with 2 ability levels each or 3 minions with 1 or 2 ability levels, but no minions with 3 or more levels. For example:

The Boss (3 shooting, 1 stalking, 4 command, 2 toughness, 1 tgh/2, 11 defense) is a street smart enforcer with a white suit and a submachine gun. He is always accompanied by four muscular, but poorly motivated thugs (1 toughness, 0 tgh/2, 10 defense) who conceal blunt weapons under their long overcoats.

Minions can continue fighting even after their leader has escaped or been incapacitated.

Combat Example

Breakhelm X-19 (1 piloting, 4 shooting, 4 fighting, 6 toughness, 3 tgh/2, 13 defense) is a notorious mutant-cyborg outlaw, wanted for piracy and industrial sabotage. He is armed with an advanced targeting system that gives him deadly accuracy with both his side arm and space ship weaponry, as well as helps him pilot space craft. Much of his body is cybernetic and armored, with retractable blades intended for use in industrial emergencies and self-defense.

Chokestar (2 piloting, 3 wrestling, 3 stalking, 2 toughness, 1 tgh/2, 13 defense) is a bounty hunter, pilot and non-lethal weapons expert. He likes to take his targets quickly and by surprise, using crafty stealth techniques to bring in live bounties. He usually wears dark-colored gear that conceals his identity.

Flipfire (2 shooting, 2 healing, 2 fighting, 2 acrobatics, 2 toughness, 1 tgh/2, 12 defense) is a medic and commando turned mercenary. She has an acrobatic fighting style that allows her to keep fighting as she leaps back and forth between fallen comrades as she attempts to revive them. She is armed with a bayoneted assault rifle and light body armor.

Chokestar and Flipfire have just stormed onto Breakhelm X-19's ship in an attempt to capture him. Chokestar goes first because he has the highest stalking ability. Flipfire and Breakhelm X-19 both have no stalking ability, so a twenty-sided die is rolled for each of these characters to break the tie. Flipfire goes next and Breakhelm X-19 goes last because her roll is 7, and his roll is 4. Each character has hit points equal to his or her toughness.

Chokestar can do two attacks with his wrestling ability: a damaging attack and a delaying attack. For his delaying attack he attacks Breakhelm X-19 with a stun gun. A twenty-sided die roll is added to Chokestar's wrestling ability, for a total of 12, which is barely not enough to reach Breakhelm X-19's defense of 13 (10 plus his tgh/2.) Chokestar's damaging attack is a combo of martial-arts strikes. A die roll is added to his wrestling for a total of 13, which is barely equal to Breakhelm X-19's defense, so Breakhelm X-19's hit points are lowered from 6 to 5.

Flipfire takes a shot at Breakhelm X-19 with her rifle. A die is added to her shooting for a total of 10, which is not high enough to reach Breakhelm X-19's defense, so her bullets fail to penetrate his armor. (This also causes one point of damage to Breakhelm X-19's ship according to the Vehicle Rules below.)

Breakhelm X-19's retractable blades come out, and he slices away at Chokestar. A die roll is added to Breakhelm X-19's fighting ability for a total of 18, which injures Chokestar by lowering his hit points from 2 to 1 so that they are equal to his 1 tgh/2. Breakhelm X-19 can do a second fighting attack, so he tries to finish off Chokestar while he can. A die roll is added to Breakhelm X-19's fighting ability, for a total of 14, so Chokestar is tossed to the side incapacitated with 0 hit points.

Chokestar does nothing on his turn because he is incapacitated.

Flipfire leaps to Chokestar's aid, injecting him with adrenaline and leveraging him back to his feet. Flipfire's healing ability is added to a die roll for a total of 14, which is equal to or greater than the 10 difficulty of reviving a character. This restores Chokestar to 1 hit point, so he is injured rather than incapacitated.

Breakhelm X-19 takes careful aim at Flipfire and fires. A die roll is added to his shooting ability for a total of 11, which only grazes Flipfire causing her no damage because it does not quite reach her 12 defense (10 plus her acrobatics ability.)

Chokestar again tries to stun Breakhelm X-19. Chokestar's wrestling ability plus a die roll comes to 15, reaching and surpassing Breakhelm X-19's defense, so Breakhelm X-19 is delayed until the end of his next turn as he shakes off being stunned. Chokestar does not get a second wrestling attack because he is injured.

Flipfire takes another shot at Breakhelm X-19. Her shooting ability plus a die roll comes to 19, lowering Breakhelm X-19's hit points to 3, and injuring him because his remaining hit points are not greater than his 3 tgh/2.

Breakhelm X-19 does nothing on his turn because he has been delayed by a hit from Chokestar's stun gun.

Chokestar chooses to attack Breakhelm X-19 with a damaging strike instead of stunning him again. Chokestar's wrestling ability is added to a die roll for a total of 16, which is equal to or greater than Breakhelm X-19's defense, lowering his hit points to 2.

Flipfire takes another shot at Breakhelm X-19. Her shooting ability plus a die roll reaches or exceeds Breakhelm X-19's defense, his hit points are lowered to 0 and he is incapacitated. The bounty hunters are victorious.