Metroidvania

1) Loosely defined, "Metroidvania" is supposed to be a 2D video game style in which the gameplay is focused on considerably non-linear exploration, item retrieval and proper usage of these items in order to fulfill the game's primary objective and achieve the desired outcome. A combination of "Metroid" & "Castlevania" coined after "Symphony of the Night" (Castlevania game) because of the exploration aspect of the game. It's a stupid term because games that could be described this way were around before there was ever a Metroid or Castlevania game. Just a very short list of games that could arguably be classified as Metroidvania or have similar exploration and/or action credited to Metroid that were released well before or around the same time as Metroid: