# MVP Survival And Readiness Criteria

This document locks the early MVP target for time, survival pressure, player
success, failure, and closed-test readiness.

## Day And Night

MVP rule: day/night presentation should mimic the real Earth region represented
by the loaded map tile, while the gameplay calendar uses the MVP pacing target
of `4 real hours = 1 in-game day`.

For Ground Zero, weather and sunlight should come from the same real-world tile
context so the player feels like they are standing in that place. The sky should
respect the region's local time zone, sunrise/sunset shape, season, and weather
direction as the system matures, but the MVP gameplay day is still compressed
to four real hours so players can experience a full survival cycle in a
reasonable test session.

Implementation target:

- The server owns time and replicates it to clients.
- The MVP gameplay calendar target is `4 real hours = 1 in-game day`.
- Ground Zero day/night presentation uses the real local time zone and regional
  solar/weather context for its real-world coordinates.
- Sunrise, sunset, day length, night length, and seasonal light should be based
  on the tile location as the system matures.
- The MVP fallback can use the accelerated 24-hour gameplay clock with
  conservative fixed night bounds until real sunrise/sunset lookup is
  implemented.
- Additional time acceleration is allowed for test commands and automation, but
  should not replace the default four-hour MVP day for normal playtests.

Design consequence:

- The sky stays regionally grounded even while the gameplay day is compressed.
- Skills, tools, teamwork, shelter, storage, domestication, and infrastructure
  improve what players can accomplish inside the compressed gameplay calendar.
- Natural biological systems should not be casually compressed just to make
  progress feel faster.

## Survival Pressure Target

The first playable MVP should feel difficult but learnable.

Target experience:

- A new solo player can survive the first session by gathering, drinking,
  crafting a basic tool, making fire, and using shelter.
- Ignoring hunger, thirst, cold, injury, or weather can kill the player.
- Death should usually feel preventable after the player understands the rules.
- Early play should be inefficient and hands-on.
- Progress should noticeably reduce friction through better tools, storage,
  shelter, food access, water access, and knowledge.

Early survival pressure should come from:

- thirst and freshwater access;
- hunger and low-yield gathering;
- cold exposure, especially at night or in bad weather;
- injury/damage;
- fire and shelter reliability;
- limited inventory and carrying capacity;
- weather changing the risk profile.

## Basic Success Loop

The MVP loop is complete when a player can:

1. Spawn into the Ground Zero tile after the startup and character-selection
   flow.
2. Read the environment enough to find immediate resources.
3. Gather primitive materials.
4. Drink or collect water.
5. Craft at least one useful primitive tool.
6. Make or use fire.
7. Build or use a primitive shelter.
8. Survive weather and nighttime pressure.
9. Store or preserve some useful progress.
10. Leave and return after restart with core state preserved.

The loop should show the intended long-term direction: survival starts with
hands, improvised tools, and local knowledge, then moves toward better tools,
storage, shelter, domestication, farming, logistics, and cooperation.

## Failure Conditions

The MVP should support clear player failure states:

- death from health reaching zero;
- dehydration;
- starvation;
- cold exposure/hypothermia;
- injury or damage;
- inability to recover after poor preparation for night/weather.

For MVP, failure does not need a complete generational inheritance system.
Respawn rules can be simple, but death should still cost enough to make survival
matter.

## First Playable Internal Milestone

The first playable internal milestone is ready when:

- one Ground Zero tile loads as the playable map;
- the map uses the Ground Zero tile context for time/weather direction;
- the player can gather, drink, craft, make fire, and use shelter;
- hunger, thirst, body temperature, and health can all affect survival;
- one meaningful death path works;
- core state survives a server restart;
- the startup flow reaches character selection before entering the world;
- two players can join the same server for a basic multiplayer smoke test.

## Closed-Test Readiness

Closed testing can begin when:

- the Windows build installs and launches on a clean test machine;
- the public or LAN tile endpoint is stable for the test group;
- onboarding tells players enough to start without exposing debug internals;
- at least one full day/night survival test passes;
- basic telemetry/logging is available for crashes and major failures;
- known critical bugs are documented;
- reset/recovery instructions exist for the test server;
- testers can report bugs with build version, map tile, and reproduction notes.

## Explicit Non-Goals For This MVP

Do not block first playable MVP on:

- full Earth-scale streaming;
- full real-weather provider integration;
- full sunrise/sunset astronomy accuracy;
- mature farming/livestock life cycles;
- full economy or AGR utility;
- full generational succession;
- polished character art;
- public Steam/Epic release readiness.

## Scope Gate

The detailed six-month MVP scope, exclusions, player-count target, and
acceptance checklist live in:

```text
Docs/SixMonthMvpDefinition.md
```
