RPG Design Patterns

Alignment, Class Tree, Game Master, Generalized Contest, Gift, Faction (based on various alignment categories), Hit Points, Last Man Standing, Race, Rank, Resource (money), Random Attribute, Skill, Success Reward

Characters have six primary attributes (“Abilities”) of “Strength,” “Dexterity,” “Constitution,” “Intelligence,” “Wisdom,” and “Charisma” whose values are generated by random dice rolls. Players must choose a race for their character as “Dwarf,” “Elf,” “Gnome,” “Half-Orc,” “Half-Elf,” “Halfling,” or “Human” (other possibilities also exist). The race provides adjustments to the basic attributes along with a variety of other gifts. Each character has a small number of classes, usually one, chosen from options such as “Fighter,” “Monk,” “Rogue,” and “Wizard.” Each class gives a character access to special abilities, which improve as the character gains levels by accumulating experience points. Skill ranks, whose costs are set by the character’s class, and gifts (“Feats”) are also gained as characters gain levels. Characters accumulate “Hit Points” as they gain levels by rolling dice and adding in adjustments for Constitution. The character’s class determines the size of dice used.

Task resolution is determined by having a player roll a single d20. When a character uses his skills, the player adds various attribute and skill bonuses, and compares the result to a threshold. The result indicates either success or failure. If the character is attempting to strike an opponent with a weapon, various modifiers are added to his roll, including the character’s “Base Attack Bonus,” pertinent attribute bonuses, size modifiers, and other miscellaneous modifiers. This is compared to the target’s “Armor Class,” which comprises the character’s “Armor Bonus,” “Shield Bonus,” “Dex Bonus,” “Natural Armor,” and other miscellaneous bonuses. If the blow lands, the player then rolls dice to determine damage depending on the weapon used. If the d20 roll was high enough, the weapon may do double or triple damage.

Initiative is determined by having each combatant roll a d20 at the beginning of melee and adding adjustments based on attributes and gifts. The order then proceeds in a round-robin fashion until the conflict ends. A host of rules control what actions (and how many) are allowed on each player’s turn.

D&D rewards players by giving their characters experience points and treasure for defeating foes. The experience points accumulate to determine a character’s level. The treasure is either used directly, if it has its own in- game purpose (such as a Ring of Invisibility or a Wand of Fireballs), or is used to purchase items that enhance the group’s ability to slaughter ever more powerful unsuspecting beasties.