Exploratory video game

When referring to video games, the descriptor exploratory video game usually means that previously-played areas of the game can be revisited, and gameplay often involves finding unreachable paths, and returning to them later in the game with items or abilities that will make them accessible. Usually, by the end of an exploratory game, the player has access to every part of the game world.

Completion of game
Additionally, exploring in general is often rewarded in this style of game, with an award for "perfect completion" only available if the player has completely scoured the game world, travelled every path and gotten every item. Some exploratory video games also include very powerful items or abilities that are not necessary to complete the game, and can only be obtained via very difficult side quests.

Some exploratory games (the Metroid series, for instance) have completely contiguous worlds, while others have worlds broken up into sections, usually designated by points on a map.

Genres
Exploratory video game genres include:
 * Isometric adventure games
 * Metroidvanias
 * Roleplaying video games

Game series
Exploratory video game series include:
 * The Legend of Zelda
 * Metroid
 * Castlevania (beginning with Castlevania: Symphony of the Night)
 * Final Fantasy
 * Mega Man X