keys in game design

Keys are a common feature of loads of different sorts of games, but there is a great deal of diversity in the way in which they can be implemented. In earlier game such as Adventure for the Atari 2600, keys as a game mechanic were very literal. In Adventure, the yellow key opened the yellow door, the black key opened the black door, etc.


Needing to block off certain areas of play is a common necessity for many designs, but the use of a key can be integrated into the story. In Rachet and Clank by Insomniac, ‘keys’ are primarily implemented in two different ways:


One way that areas are made inaccessible is by keeping the player ignorant of the location altogether. Until a player finds an ‘infobot’ (in area that is already accessible), the player does not know that the corresponding area exists. The infobot then plays a movie which informs the character (and the player) of the newly accessible area.


The other way that areas are made inaccessible is by having items that serve as keys for progression within a particular map. The interesting thing is that the item is almost never a key. An ‘O2 mask’ will let the character into places that he couldn’t breathe earlier (like a gassy planet or prolonged time underwater). Magnetic boots allow the character to traverse bridges formerly inaccessible with a satisfying aesthetic twist. These items (and countless others) serve as keys in the gameplay sense.