Design reference index · 10/27
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Procedural Content Generation
Generating maps, items, or events using rules, algorithms, and input parameters.
Emergent Gameplay
Behavior arising from combinations of rules rather than being explicitly prescribed by the designer.
Sandbox
A play structure emphasizing systems and freedom of choice over a fixed progression order.
Permadeath
A rule in which death permanently removes some or all character or progression state.
Checkpoint
A reference point for returning after failure or saving progress.
Save State
Stored world, character, and progression data that allows play to resume.
New Game Plus
A mode restarting a completed game while retaining some progress or equipment.
Vertical Slice
A small representative segment implementing the core experience at the intended quality level.
Game Design Document
A living planning document sharing specifications for rules, experience, content, and systems.
Hitbox
A spatial region used to determine whether an attack contacts a target.
Hurtbox
A spatial region used to determine whether a target receives an attack.
Collision Shape
A simplified shape used for physical collision or overlap tests.
Invincibility Frames
A period during an action in which damage cannot be received.
Startup Frames
The interval from an action's start until its attack becomes active.
Active Frames
The interval during which an attack's hit detection is active.
Recovery Frames
The interval after an attack's active phase during which subsequent actions remain restricted.
Hitstun
A temporary restriction on a target's actions after being hit.
Hit Stop
A brief pause in movement or time at impact to emphasize the force of a hit.
Knockback
An effect that pushes a target's position or velocity away from an impact.
Telegraph
A pre-attack cue using motion, color, or sound to communicate danger and response timing.
Parry Window
The interval in which an input is accepted as a successful parry.
Input Buffer
A mechanism storing an early input briefly and executing it when the action becomes available.
Coyote Time
A short grace period allowing a jump just after leaving a platform.
Jump Buffer
A mechanism storing a jump input just before landing and executing it on landing.
Variable Jump Height
A design in which jump height varies with factors such as how long input is held.
Air Control
The degree to which movement direction or speed can be controlled while airborne.
Acceleration and Deceleration
Rules determining how movement speed increases or decreases with input changes.
Dead Zone
An input range that ignores minor unwanted input fluctuations.
Aim Assist
A feature adjusting aim movement or target selection within defined limits.
Lock-on
A feature maintaining aim, camera, or movement relative to a selected target.
Cooldown
The delay after using an ability before it can be used again.
Stamina System
A system regulating consecutive actions through a resource that is spent and recovered.
Animation Cancel
A rule allowing a current animation or action to be interrupted and transition to another action.
Combo System
A combat structure linking consecutive inputs or actions under defined conditions.
Time to Kill
The time needed to eliminate an opponent under specified conditions.
Damage Falloff
A rule reducing damage based on attack distance or other conditions.
Friendly Fire
A rule allowing a player's attacks to affect allies.
First-person View
A view of the world from the controlled character's eyes or a nearby position.
Third-person View
A camera view outside the character that shows both the character and their surroundings.
Top-down View
A viewpoint looking downward onto the play space.
Side-scrolling
A presentation organized around horizontal or side-on movement.
Orthographic Projection
A projection preserving parallel lines and apparent size independently of distance.
Perspective Projection
A projection conveying depth by making more distant objects appear smaller.
2.5D
An informal category combining 2D and 3D presentation or gameplay constraints.
Roguelike
A genre family sharing features associated with Rogue, such as procedural generation and death-related loss.
Roguelite
An informal category combining roguelike repetition with softened structures such as persistent progression.
Metroidvania
An interconnected exploration structure in which new abilities change access to previously visited areas.
Immersive Sim
A design tradition emphasizing consistent interacting systems and multiple solutions to problems.
Survival Crafting
A structure combining resource management, survival constraints, gathering, crafting, and base expansion.
RTS
A strategy structure coordinating resources, units, and commands while time continuously advances.
Turn-based Strategy
A structure executing decisions in a specified action order or in discrete turns.
Tower Defense
A structure preventing enemy passage through placement and upgrading of defenses.
Deckbuilding
A core mechanic in which players modify a collection of cards and develop combinations during play.
HUD
An interface persistently presenting information needed during play.
Diegetic UI
Information presented as an object within the game world that characters could also perceive.
Non-diegetic UI
An interface visible to the player but not existing as an object in the game world.
Spatial UI
Information positioned in world space that may not exist as a physical object in the fiction.
Meta UI
Screen effects such as blood or blur communicating world state; usage varies across classification systems.
Reticle
The general marker system expressing aim position and aiming state.
Health Bar
An interface showing remaining health or durability, commonly as a bar.
Damage Number
Text feedback displaying the amount of damage dealt by a hit.
Quest Marker
A marker identifying where a quest starts, progresses, or completes.
Interaction Prompt
A contextual interface displaying an available action and its input key.
Inventory Grid
An interface arranging, sorting, and managing items in grid cells.
Hotbar
A row or area of slots for quickly activating frequently used items or abilities.
Radial Menu
A menu arranging options radially around a center.
Fog of War
A system concealing map or enemy information according to exploration and visibility conditions.
Finite State Machine
A model representing behavior through predefined states and transition conditions.
Behavior Tree
A tree combining condition, selection, and sequence nodes to determine agent behavior.
Utility AI
An approach choosing an action by scoring available options for the current situation.
GOAP
An AI approach planning action sequences from goals, preconditions, and effects.
Blackboard
A shared store of variables and observations used in AI decision-making.
Steering Behavior
Algorithms combining pursuit, avoidance, separation, and related rules to determine movement direction.
Perception System
A system detecting targets or events through vision, hearing, distance, and related signals.
Aggro
An enemy's attention or attack-target state and the rules governing target selection.
Spawn System
A system managing where, when, and under what conditions enemies or items appear.
Encounter
A meaningful confrontation or combat situation combining enemies, environment, and objectives.
Narrative Design
Designing how a story is communicated through rules, spaces, and interactions.
Branching Dialogue
A dialogue structure whose lines and outcomes branch according to choices and state.
Quest Graph
A node graph representing quest conditions, objectives, dependencies, and branches.