Hargob

Full Game Vision

High Concept

Hargob is a rhythm-action game with an emergent musical soundtrack. Enemy movement, telegraphs, hitboxes, and recovery share the same musical timing. The player learns an enemy's phrase, dodges it, and answers on beat.

1. The enemy telegraphs an attack phrase.
2. The player dodges spatially and, ideally, rhythmically.
3. A rhythmic dodge builds Momentum and opens a counter window.
4. The player counters immediately or banks Momentum.
5. A counter releases all stored Momentum on impact.

Lore and Background

For thousands of years, the Knights of the Eastern Salts have expanded through Arc-Harmonic Technomancy, the study and arcane manipulation of universal rhythms such as planetary orbits, tides, and organism lifecycles.

One of their machines unintentionally accelerates the tide cycle, washing strange deep-sea creatures and vibrant, humming Sea Slugs onto the coast. After eating the contaminated slugs, Hargob and several coastal goblins develop a never before seen Arcane Harmonic Intuition: the ability to perceive attacks, movement, and magic as musical structure.

This intuition is the in-world basis of the rhythm-action gameplay. Hargob can hear and feel an enemy's movement, anticipation, attack, and recovery as parts of a phrase.

Aesthetic tone

Hargob ventures through a shifting coastal region to challenge the Knights for their oppression of the goblins. Coastal creatures encountered along the way are warped and naturally very aggressive as a result of the tidal acceleration. The goblins are naturally goofy and unserious, contrasting with the Knights' grand, self-important character. Sea Slugs carry the same tonal contradiction: they are the contaminated source of Hargob's power, but are also treated as cheerfully delicious rewards.

The Flat One

Eating enough slugs leaves a goblin profoundly stoned. While lying back and staring upward, they see the sky's dome flatten into a projection and hear the stars speak. This is communion with The Flat One: simultaneously the flattened sky, a fourth-wall reference to the display, and a goblin's dim awareness of The Player watching and guiding them.

Player Experience

Hargob should feel like playing a feral but feeble little guy: weak in direct exchanges but willing to charge into danger, redirect rhythmic energy, and unleash devastating counters.

Combat should equally reward:

• Learning an enemy's rhythm and patterns.
• Executing spatial and rhythmic dodges.
• Feeling tension rise with Momentum before a counter releases it.

Ordinary action-game play remains valid, but rhythmic mastery wins faster and intensifies the audiovisual response.

Mechanics and Rules

Accepted engine-independent details are maintained in the Mechanics Specification. This GDD retains the intended player experience and accepted high-level rules. Prototype behavior is not canonical unless it passes the human-approved mechanics decision workflow.

Core Combat Systems

Musical Transport

Combat uses one authoritative audio clock. Gameplay queries beat-relative musical position rather than maintaining an unrelated combat timer.

Movement, Dodge, and Counter

Movement is continuous and never waits for a beat.

Hargob may attack at any time. Outside an earned counter window, the enemy blocks but still receives chip damage. During the next-beat counter window, the player may attack immediately or skip it and retain Momentum for a stronger later counter. Every counter consumes all stored Momentum, with damage and impact scaling to the amount released.

Momentum

Momentum represents Hargob redirecting rhythmic energy and taking control of the musical exchange.

Spatial-only dodges and ordinary blocked attacks add no Momentum. Presentation changes smoothly rather than jumping between visible tiers.

Incant System

Incants are a full-game alternative use for a completely full Momentum meter, tested first through the current Phaser prototype:

Full Momentum → Draw and Pin → Perform to Select → Resolve or Interrupt → Consume or Partially Deplete

Core rules:

• A separate draw button offers three Incants from an encounter-scoped deck of 10 static Incants. The offer remains available for four transport beats before expiring.
• Drawing at full Momentum commits and pins the full meter. Pinned Momentum does not decay and cannot power a counter or another spend.
• Three stable buttons belong exclusively to Incant phrases. Movement remains available; combat actions never count as phrase inputs.
• There is no separate card-selection input. The first Incant input starts the performance and plays its first note; the complete performed phrase selects one offered Incant.
• All deck phrases are unique and prefix-free, so no complete phrase is also the valid beginning of another.
• Attack, dodge, counter, or explicit cancel interrupts after draw. The exact offer and slot order remain reserved, while a tunable portion of pinned Momentum is depleted.
• The first connected enemy hit after draw damages Hargob but neither interrupts the Incant nor resets pinned Momentum. The second connected hit interrupts and applies the same partial depletion. Each draw resets this hit count.
• Invalid or expired input fails immediately when no offered phrase remains possible, reserves the offer, and applies the partial depletion.

Each encounter seed deterministically shuffles the deck. A successful resolution returns the two unused cards to the draw-pile bottom in stable slot order. Before a draw with fewer than three cards remaining, combine the remaining draw pile with the discard pile and reshuffle using the encounter's random sequence.

Incants inherit the encounter transport's current BPM and meter when their first input anchors the phrase. Their BPM remains fixed until resolution. Slightly early first inputs may buffer to the next eligible subdivision; later inputs compare against beat-relative positions and tolerances. Inputs grade as Perfect, Good, Early, Late, Missed, or Incorrect.

Each Incant authors its own transport-relative effect-release point. A successful tempo-transforming Incant may change encounter tempo only after its performance resolves; transformation amount, duration, transition, and restoration remain tuning. Timing assistance widens performance tolerances while reducing effect strength.

The draw plays a common offer accent, each dedicated input sounds its note immediately, and phrase completion plays the resolved Incant's identity or release accent. Static Incants are the initial supported type; generative and expressive recognition remain deferred.

Feedback Principles

Feedback must distinguish enemy intent, spatial versus rhythmic dodge results, counter availability, Momentum state, blocked versus counter damage, and encounter outcomes. Sound, animation, hit reactions, particles, screen effects, HUD, color-independent symbols, and optional controller response may reinforce those distinctions. The most polished event should be a Momentum-scaled counter.

Overall Direction

• Multiple enemies with distinct musical identities.
• Authored motifs assembled into changing phrases and a larger musical difficulty grammar.
• Sea Slugs as persistent reward and currency.
• A Hades-inspired run and base-camp structure.
• Communion with The Flat One to purchase Incants.

These establish the intended identity, not the current prototype scope.

Current Prototype

Prototype Contract

The Phaser prototype tests whether one readable musical attack can produce a satisfying dodge, Momentum build, counter release, and full-Momentum Incant alternative.

The template enemy blocks ordinary attacks, uses no adaptive AI, and repeats its authored static phrase. Runtime consumers must load phrase events from authored JSON under root content/, validate the semantics they require, and must not define alternate phrase defaults; this GDD does not define event positions. Exact BPM, timing windows, movement speed, dodge distance, decay rate, damage, and feedback curves remain tuning variables.

Technical Direction

Musical transport remains independent of rendered frame timing to prevent audio and combat drift.

Out of Scope

The first prototype excludes multiple enemies or arenas, multiple or procedural enemy phrases, dynamic musical grammar, generative or expressive Incants, progression, runs, base camp, the Sea Slug economy, narrative campaign content, the Knights' stronghold, and production latency calibration.

Development Agents

Development work separates deterministic transformations from agent judgment. Exporters, scaffolders, JSON parsing, consumer semantic checks, timeline generation, telemetry capture, metric calculation, and output guardrails are ordinary code. Agents interpret, create, prioritize, and propose; they do not replace those tools.

Enemy Phrase Production Agents

Combat Playtest and Balance Agents

Phaser and Godot may produce the same future engine-neutral telemetry contract through separate adapters. Deterministic preprocessing validates and groups sessions, calculates metrics, and reports data quality. Deterministic postflight checks evidence references and tuning limits, then writes proposed artifacts under ignored output directories. Agents never apply tuning or edit source.

The coordinated loop is:

Human brief → phrase agents → human Ableton authoring → deterministic export
and validation → human playtest → deterministic evidence preparation →
playtest agents → human approval

Players experience the result through distinct musical enemy attacks, synchronized audio and combat events, clearer timing, and evidence-driven balance improvements.