One premise.
One complete world.

One strong player fantasy gives every other system a reason to exist.

The premise names what the player is trying to become, protect, transform, understand, or accomplish. It is narrow enough to guide decisions and rich enough to support a complete world rather than a single moment.

Explanatory archetype—not a release: Explanatory example: keep a fragile signal moving through a passage that continually changes how movement works.

Coherence test: Can the controls, spaces, progression, feedback, and ending all be explained as consequences of the same central commitment?

Primary and secondary verbs turn the premise into meaningful decisions.

The player reads a situation, acts, receives legible feedback, and adapts. Mechanics include success, failure, retry, recovery, and enough variation for mastery—not merely movement through scenery.

Explanatory archetype—not a release: Explanatory example: redirect momentum, brace at the right moment, and choose between a safer route and a more demanding shortcut.

Coherence test: Does each major action create a readable consequence and a reason to make a different choice next time?

Space is authored around play, orientation, discovery, and recovery.

The environment teaches through shape, rhythm, contrast, landmarks, hazards, opportunities, and safe recovery points. It is not a backdrop pasted behind mechanics; it changes what the mechanics mean.

Explanatory archetype—not a release: Explanatory example: a narrow threshold amplifies precision while a broad chamber invites planning and experimentation.

Coherence test: Can the player understand where they are, what changed, and where a recoverable next action exists?

The complete game develops skill, possibility, stakes, and resolution.

Progression may expand verbs, deepen combinations, transform spaces, raise demands, reveal meaning, or change how earlier systems are understood. Saving, pause, retry, normal completion, mastery, and replay value are designed as one continuity.

Explanatory archetype—not a release: Explanatory example: early spaces teach one timing relationship; later spaces combine it with route choice and resource pressure.

Coherence test: Does the Full resolve the central premise through a complete arc rather than simply extending duration?

Touch, keyboard, and pointer controls express the same player intention.

Controls are explained before they are demanded, remain reachable on phone portrait, respond visibly, and preserve alternatives when timing, precision, repeated input, or camera behavior would otherwise block use.

Explanatory archetype—not a release: Explanatory example: one primary action remains large and thumb-reachable while keyboard and pointer inputs provide equivalent intent.

Coherence test: Can a visitor understand the objective, act, pause, recover, and continue without relying on one device or sensory channel?

Visuals, interface, music, ambience, and sound describe the same world.

The audiovisual system clarifies state, consequence, scale, atmosphere, and progression. It is concept-native rather than a genre skin, remains optional where appropriate, and never hides required information behind sound or effects.

Explanatory archetype—not a release: Explanatory example: a low foundation communicates scale while a restrained upper signal marks successful alignment; both have visible equivalents.

Coherence test: Do quiet, reduced-motion, reduced-effects, and audio-off states preserve the complete meaning and route through the world?

A release is complete only when its behavior and public claims are directly supported.

The highest-risk mechanics and sensory direction are proven in a near-final Golden Vertical Slice. The complete product is then checked across input methods, viewports, save and recovery paths, accessibility states, resources, rights, packaging, and truthful Demo/Full boundaries.

Explanatory archetype—not a release: Explanatory example: a failure path is verified through retry, reload, restored state, and normal completion—not merely observed once in an ideal path.

Coherence test: Can every public promise be traced to directly verified behavior, delivery evidence, or an explicitly bounded external dependency?