User:MentalMouse42/Overview

This is meant to be an overview of Minecraft, not from the pure newbie's or munchkin's point of view, but for someone who thinks of games in terms of structure and balance.

Basic structure
Minecraft is a hybrid game. Its original form was as a "sandbox" game, in which the player has pretty free reign to manipulate the world. However, it has since acquired an "adventure" component as well, in which the player is confronted by both the need (or desire) for certain resources, and hazard from various threats. There are three major game modes, each of which offers different emphasis on these two aspects of the game. Any of these modes can be played in single-player or multi-player modes. There are also both built-in features ("flatworld") and external "game mods" which can drastically change gameplay; I will not be discussing these.

World Structure
All the game modes share the same basic world structure: A grid matrix of cells (in-game, "blocks"), which is finite vertically, but which is automatically extended horizontally as the player(s) move about. In general, this generation happens far enough from the player to be invisible to them, though a rapidly travelling player might notice some related anomalies.

Each of these blocks can be empty ("air"), can be filled with some material, or contain an object ("item block"), which is usually connected to one or more adjacent blocks. There are also "entities", objects which may move across the grid, and (unlike blocks) are usually not limited to integral coordinates. These entities include the player, "mobs" both hostile ("monsters") and friendly, occasional vehicles, and "item entities" representing blocks and items which have become detached from the matrix proper. (There are a few immobile entities which are also fixed to the grid.) The player can convert blocks into items, and collect them in the inventory for later use. The player can do various things with items: most can be placed into the world, many can be converted into different items, and some consumed directly by the player. The inventory is large, and there is no encumbrance mechanic.

Game Modes
Creative mode is the purest expression of the "sandbox" aspect of Minecraft: Resources are infinite, obstacles can be wiped away easily, and the player not only invulnerable, but has total freedom of action, including access to many "internal" game commands for manipulating the world. In this mode, players can create huge and complex structures, or experiment with the subtleties of game mechanics. Creative mode also doubles as the "build" mode for creating "custom" maps, which can be copied for use by other players.

Survival mode represents a balance between sandbox and adventure aspects, somewhat biased toward the sandbox side. The prospect of injury and death appears, and also the need for food. These are represented by health and hunger "bars" (gauges) respectively. However, most hazards are avoidable, and food is plentiful. Death results in being respawned at a fixed or previously-chosen location, while the player's items remain at their death location (where they can be lost or destroyed). Environmental hazards also appear, notably monster attacks, falling, drowning, and burning. The level of hunger affects healing: near-complete satiation allows injury to heal over time, while starvation inflicts damage. Nearly any block or object can be destroyed, but some require special tools to collect them as items. Several difficulty levels vary the level of hazard, and add or remove various dangers, including making exceptions to the above. To summarize the difficulty levels:
 * Peaceful: No monsters are present, and food is not necessary for healing.
 * Easy: Monsters appear, but with weak attacks.  Starvation will reduce the player to at worst half their maximum health.
 * Normal: Monsters attack at nominal strength, and some have special attacks.  Starvation and poison can reduce the player to minimum (non-fatal) health.
 * Hard: Monster attacks are more powerful, and starvation can kill the player outright.
 * Hardcore mode: Identical to hard mode, but the player does not respawn upon death.  That is, death is a true "game over".

Adventure mode shifts the game strongly toward the "adventure" aspect of the game. Play is always, or at least begins, on a previously prepared map, rather than on the randomly generated and unlimited map of the other modes. Similarly, destruction and collection of blocks is more tightly limited. The map provides various constraints, resource limits, and objectives, and can apply special rules or responses for player action.

Of these modes, Survival at Normal difficulty represents the "canonical" Minecraft experience, and most of the following discussions of balance and game structure will refer to this mode. (While Creative mode is popular for artistic efforts, game balance and structure hardly apply to it.)

The Gameworld
There are actually three separate grids ("dimensions"), but two of them represent advanced segments of the game. The primary dimension or Overworld is 256 blocks high, bounded above and below by regions which the player cannot affect or (normally) enter. The top half of this range, however, is not populated by the game engine, and represents space for player constructions. This gameworld mimics a natural terrain, with pseudorandom variation providing a variety of environments ("biomes") -- these vary not only in appearance, but in available resources, and in some cases, game-rule modifications. The bottom quarter of the height range is occupied by oceans and the underlying mass of the terrain, the latter riddled with caves and other gaps.

There are some global processes which occur occasionally, and simultaneously across the gameworld, but otherwise, the world is essentially static, with significant change introduced only by the player. However, parts of the gameworld can be created in unstable states, leading to changes happening shortly after generation. Due to performance considerations, all gameworld changes are limited to a certain range ("chunk update radius") around the player(s), including those processes previously begun by player action.

Discussions from this point on will increasingly refer to specific elements and contents of the gameworld.

Global Processes
All of these except the day/night cycle depend on the player's chunk update radius. (Weather technically happens outside the radius, but has no effects.)
 * The most prominent global process is the day/night cycle, which repeats every 20 minutes of play time. Night time reduces light levels, which affects not only in-game visibility, but the monster generation process described below.
 * There is also a pseudorandom variation in "weather", among "clear" weather, "rain", and "thunderstorm". The latter two impede visibility in their own right, and also reduce light levels, which again affects monster generation.
 * Thunderstorms also produce lightning, which produces a rare hazard for players, and also occasionally sets small fires on the landscape.
 * In desert biomes, neither rain, snow, nor lightning falls, but the reduction in light levels still occurs.
 * In "icy" biomes, rain and thunderstorm are replaced by snowy equivalents, which can deposit snow on the landscape and freeze surface water. This can set off other processes, mostly killing certain plants.
 * While most peaceful mobs are created with the terrain, a few are spawned afterward. Most require a minimum light level, so appear on the surface during clear days.
 * The only water mob (squid) is created in oceans as an ongoing process.
 * Hostile mobs, or monsters, are generated differently. They are created continuously, but only in darkened spaces.  Thus, they can always appear in underground caves, but on the surface they will appear primarily at night, and occasionally during thunderstorms.  This "natural monster spawning" only occurs within a certain range of some player (but is suppressed very close to them), and hostile mobs tend to despawn outside a somewhat larger range.
 * Some of these monsters (zombies, skeletons) are specifically destroyed by bright (clear-weather) sunlight, while others (spiders, Endermen) are "defused", becoming non-aggressive.
 * One type of monster (Endermen) makes occasional minor alterations to the gameworld, when present.
 * As noted above, parts of the landscape can be generated in unstable states, beginning processes which will proceed as soon as the player comes within update range of the area. These include:
 * Newly generated springs of water or lava will flow. They may form obsidian, stone, and/or cobblestone as water and lava interact.  Ocean or lake blocks may also flow into available openings to underground spaces, with similar results.
 * Some leaf blocks are generated in inappropriate places, and will die within a few minutes, perhaps dropping sapling items.
 * In Villages, Zombie sieges can occur, and kill off villagers.

Game Structure
Unlike many games, there is no advancement in the character's native abilities, only in the tools available. While there is a nominal "experience" mechanic, this is only used for creating and repairing enchanted (that is, more capable) tools, armor, and weapons. Survival mode offers no explicit mandate beyond actual survival (which is fairly easy), but the game offers an implicit "scavenger hunt": Collecting and creating various items offers new capabilities for the character. In the following, a material or item is considered "fully found" when the player has enough for immediate needs, and knows where or how to get more. For many items, even small amounts give basic capacities, but large amounts (either "farmed" or accumulated over time) give additional options.

Starting Game
The most basic "finds" are the various tool materials -- some are technically optional, but are likely to be found anyway in the course of finding later materials. In their usual order of appearance, these materials are: Wood, Stone, Coal, Iron, Gold, Redstone, and Diamond. Most of these provide more powerful tools and armor, but coal is for lighting (torches) and as a fuel for preparing other materials or items, while redstone provides some key tools (clock, map) and culminates in "redstone circuitry". Of the other, miscellaneous, items, String warrants special mention, as it is required to produce a bow.

Simultaneously with climbing the "basic materials" ladder, the player needs to collect an assortment of other items, and build up local capabilities. The most immediate need is for food -- while small amounts are available more or less immediately, several structures, and food has its own hierarchy based on the structures built to supply it: Mostly, this will be crop fields, with optional animal pens, representing "vegetable" and "meat" foods. This process involves and produces a number of other materials as well. There are several different "crafting" mechanisms, but only two appear in the starting game: "crafting proper", and smelting.

Initial key items and structures:
 * Wood: Immediately provides the Crafting Table which allows for complex tools, and also sufficient for both the minimal "pole tools".  (Smaller amounts are combined with other materials for more advanced tools.)  As more is accumulated, a variety of utility items come into play, notably chests (storage) and fences (for both protection and farming).
 * Coal/Charcoal: Provides torches, the basic (and cheapest) light source.  Used to cook meats for greater nutrition and safety.  Later required to smelt (inter alia), iron and gold ore for later use.
 * Stone: Provides second-tier tools, which will remain useful later in the game as "disposable tools".  Also provides the furnace, used for smelting.
 * Seeds allow wheat farming (producing wheat and more seeds), and can be used directly for chicken breeding.
 * Wheat is used for bread, and later to capture and breed cows and sheep.
 * Cows produce meat and leather.
 * Leather is used for various advanced purposes, mostly in the middle game.
 * Eggs are used to produce chickens.
 * Chickens not only provide meat, but also feathers, which are needed to produce arrows.
 * Gravel produces flint, also needed for arrows. Flint also allows a tool to create fire at will.
 * String: Usually gotten from spiders, this allows production of bows and fishing rods.

Early Game
As the player attains basic food security, bow and arrows, and iron equipment, they move from the starting game into the "early game", where they can continue to build their capabilities, adding more options for food and equipment.
 * Iron: Provides effective (mid-range) tools and armor, and an additional group of miscellaneous tools.
 * Water: Requires iron (buckets) to manipulate effectively, used for crop farming, vertical travel, and other utility functions.
 * Fishing is one of the few ways to accumulate large amounts of food without building a farm.
 * Bows, of course, allow ranged attacks against monsters, notably the dreaded creeper.
 * Bones: From skeletons, allows accelerated growth of crops and other plants.
 * Carrots and Potatoes: Initially likely to come from zombies, these represent additional food crops.
 * Potatoes, when baked, provide a more plentiful and efficient food than bread.
 * Carrots, besides being edible in their own right, allow capturing and breeding pigs.
 * Pigs provide meat, and can later be used for transportation.
 * Wool: Various utility purposes, but initially used to produce a Bed to choose the player's spawn point.  Getting more than the small amount used for the bed, requires wheat and iron, and usually wood as well.
 * Saplings: Allows tree farming for larger wood supplies.

During this phase, the player is likely to encounter one or more villages, which allow trading for various items. This trading can shortcut the search for many of the early-game items, and can provide small amounts of certain midgame items. This phase brings in the third crafting system, where enchanting tables and anvils create and maintain enhanced tools, armour, and weapons. As the player explores and builds, they will acquire more of the basic and miscellaneous "targets", providing various additional capabilities.
 * Gold: Provides clocks and miscellaneous tools for later parts of the game.
 * Redstone: Compasses, (thereby maps), and the variety of capabilities offered by redstone devices and circuits.
 * Leather: Used for books (needed for later enchanting) and some utility items.
 * Diamonds: Provides the highest tier of tools and armor, and is doubly required for enchanting.
 * Obsidian: Requires diamond to mine, used to gain enchanting capability, and later to enter the Nether.
 * Lava: Various utility purposes, and occasionally useful for defense.
 * Sugar cane: Paper for maps and books, sugar for recipes and midgame brewing.  Boosting an enchanting table to full power, or use of multiple maps, will require enough to warrant at least casual farming.
 * Larger quantities of wood, iron, and coal, allow greater use of various tools, making it possible to, e.g. surround a village with a protective fence, or lay minetracks across great distances. Quantities of iron in particular allow for producing iron golems and heavier use of iron tools.

Some items aren't really required at this stage, but provide useful capabilities, or will do so in the midgame or later:
 * Pumpkins: Better light source/trail marker, protection from Endermen, potential food, later used for golem production.
 * Cocoa beans: Minor food role, notably cookies.
 * Melons: Disproportionately difficult to find, these provide some food (competing with cookies), but are more important for midgame brewing.
 * Tamed "dogs" and "cats", for defense. These are each found in specific biomes, and require respectively bones and fish to tame.
 * Sand: Used to produce glass and explosives.  Glass is required for all brewing, and convenient for other purposes.
 * Gunpowder: Explosives and midgame brewing.
 * Snow: Used for snow golems (defense) and incidental purposes.
 * Various Dyes: Used for decoration and signage, most often with wool.
 * Clay Bricks: Essentially decorative purposes.
 * Saddles: Allows use of pigs for transportation.  Very scarce.

Middle game
Minecraft's midgame begins with constructing and using a Nether Portal to access the Nether. This allows access to a new group of materials and their associated capabilities. Most prominently, finding and "beating" a Nether Fortress allows brewing of potions, by use of "restricted" materials which are only found there (other brewing ingredients will generally have been found in the early game):
 * Blaze Rods: "Key" item for brewing capability, also used for certain potions and to produce Eyes of Ender.  Fortress only, requires fighting a new monster.
 * Eyes of Ender: Allows limited access to an extra inventory, and can guide the player to the optional endgame.
 * Nether Wart: Also required for most potions.  Fortress only.
 * Wither skulls (Fortress only, fight a new monster): Rare item granting access to an optional boss fight.
 * Glowstone: Brighter light, used to enhance potions.
 * Soul Sand: Useful for traps and needed to farm Nether Wart.
 * Nether Quartz (As of version 1.5): Allows certain advanced redstone devices, also decorative uses.
 * Ghast Tears (fight a new monster): Used for healing potions.

Exploration of the Nether also adds a rapid-travel capability for moving between Overworld locations.

End Game
While there is no particular requirement to face it, there is an optional "boss" fight which is recognized by the game and generally positioned as finishing the game. This requires using Eyes of Ender to locate a Stronghold and use the End Portal within, to reach "The End" and fight the Enderdragon. (And that's what I mean by "positioned as finishing the game"....) No new capabilities are gained by this, but many of the prior capabilities are required to complete The End.