# V4 — Features (Page Index)

This directory holds the V4 (a UE5 tactical-action universe of multiple
game-style "cells") feature map, decomposed from the single
[`../V4_features.md`](../V4_features.md) hub into focused, in-depth,
code-grounded pages. The hub remains the canonical entry point and preserves
every section heading; each page below expands one part of the product with
richer, code-grounded detail and an honest implemented / spec-only status. The
companion architecture reference lives in
[`../architecture/`](../architecture/README.md).

> **Cross-reference convention.** Page-to-page links are relative
> (`./<slug>.md`); the architecture companion for a feature page is linked as
> `../architecture/<slug>.md`. Platform-foundation links point at the shared
> [`platform/`](../../platform/overview.html) space.

## Feature landscape

```mermaid
flowchart TB
  Promise[V4 multi-cell tactical-action promise] --> Cells[Five differentiated ruleset cells]
  Cells --> FPS[Tactical FPS]
  Cells --> Stealth[Stealth and real-time tactics]
  Cells --> ARPG[Action RPG]
  Cells --> RTS[Real-time strategy]
  Cells --> Arcade[2D run-and-gun]
  FPS --> Shared[Shared cross-cell engine]
  Stealth --> Shared
  ARPG --> Shared
  RTS --> Shared
  Arcade --> Shared
  Shared --> Modes[Campaign co-op PvP horde training replay and signature modes]
  Shared --> Product[Creator community online progression vault and live service]
  Modes --> Platform[Accessibility localization hardware trust operations and launch]
  Product --> Platform
```

The landscape makes V4's central contract visible: one reusable platform hosts
five products with different feel. Shared gameplay and services reduce
duplication, but each cell retains its rules, camera, input, AI, content, and
acceptance evidence.

Use this index by selecting the player-visible cell or cross-cell job, pairing
it with the owning [architecture topic](../architecture/README.md), and then
checking backlog, dependencies, current assets/code/tests/builds, product
review, verification, and platform evidence. A plugin or shared system proves
only its boundary; support requires the complete cell journey and applicable
cross-cell regression coverage.

Every focused feature page appears exactly once below. The
[V4 documentation guide](../docs/README.md) provides role-based paths and the
cell-aware truth model, while the [diagram atlas](../docs/diagram-atlas.md)
provides topology, action, data, state, composition, production, and release
views. Cross-cutting links add context without creating competing canonical
homes.

## Orientation

- [Product Promise & Conventions](./product-promise-and-conventions.md) — what
  V4 commits to as a multi-cell tactical-action universe.
- [Subsystem Glossary & Plugins](./subsystem-glossary-and-plugins.md) — every V4
  subsystem mapped to code, and the plugin/cell structure.

## The Cells

- [The Tactical FPS Cell](./cell-tactical-fps.md) — the tactical
  first-person-shooter cell.
- [The Stealth & Real-Time-Tactics Cells](./cell-stealth-and-real-time-tactics.md)
  — the stealth and real-time-tactics cells.
- [The Action-RPG (Wukong-Style) Cell](./cell-action-rpg-wukong.md) — the
  soulslike action-RPG cell.
- [The RTS (StarCraft & AoE-Style) Cell](./cell-rts-starcraft-and-aoe.md) — the
  real-time-strategy cell and its deterministic sim.
- [The 2D Run-and-Gun (Arcade) Cell](./cell-2d-run-and-gun.md) — the 2D
  run-and-gun / arcade cell.
- [The Shared Cross-Cell Engine](./shared-cross-cell-engine.md) — the shared
  systems every cell reuses.

## Modes & Content

- [Game Modes: Campaign, Co-op, PvP & Horde](./game-modes-campaign-coop-pvp-and-horde.md)
  — the core mode catalog across cells.
- [Training, Replay, Signature Modes & the AI Director](./modes-training-replay-signature-and-ai-director.md)
  — training, replay, signature modes, and the AI director.
- [Content, Creator Tools & Community](./content-creator-and-community.md) — the
  content/creator tools and community features.

## Online & Live Service

- [Online Services, Networking & Esports](./online-services-networking-and-esports.md)
  — online services, networking features, and esports.
- [Live Service, Progression & the Vault](./live-service-progression-and-vault.md)
  — live service, progression, and the vault/store.

## Platform, Trust & Launch

- [Platforms, Operations & Hardware](./platforms-operations-and-hardware.md) —
  platform support, operations, and hardware/peripherals/XR.
- [Trust, Safety & Compliance](./trust-safety-and-compliance.md) — trust/safety
  and compliance.
- [Narrative, Extras & Launch](./narrative-extras-and-launch.md) — narrative,
  extras/codex, and launch readiness.