Passage: Metroidvania games generally feature a large interconnected world map the player can explore, though access to parts of the world is often limited by doors or other obstacles that can only be passed once the player has acquired special items, tools, weapons or abilities within the game. Acquiring such improvements can also aid the player in defeating more difficult enemies and locating shortcuts and secret areas, and often includes retracing one's steps across the map. Through this, Metroidvania games include tighter integration of story and level design, careful design of levels and character controls to encourage exploration and experimentation, and a means for the player to become more invested in their player character. Metroidvania games typically are sidescrolling platformers, but can also include other genre types. Though popularized during the early console generations, the genre saw a resurgence starting in the 2000s due to a number of critically praised, independently developed games.

Question: What type of items a player needs to find in order to access locked areas of the map?
, tools, weapons or abilities within the game