Playdead's premiere title presents a much darker and more indeterminate interpretation of the model in question. While Super Meat Boy and Shovel Knight featured endearing parodies and humorous references to classic 2D games, LIMBO draws parallels with only a few (or perhaps one) of these games with a grim subtlety. The two previous examples certainly featured simplistic stories, but LIMBO's plot sets the standard.
Uncertain of his sister's fate, a boy enters the unknown.
True to its word, any further details of this game remain unascertained. Such ambiguity always leads to speculation and interpretation, and with LIMBO's popularity, many fan theories about the game's meaning have been circulating the internet since its release. Some adopt a more literal school of thought, believing the Boy and his Sister have entered a post-mortem reality where they must atone for their sins. Others believe the gameworld represents the Boy's greatest fears manifested to extremes (e.g. giant freakin' spiders), and that he must face them head on in order to save his sister. One of the more morbid theories identifies the Boy as the antagonist, referring to the actions of the other children in LIMBO and the game's title screen as evidence.
Though each of these hold validity in their own respect, one critical element unites each theory behind this game: the sister. No matter where the boy is or how he got there, his quest remains unequivocal. Similarly, in Super Mario Bros, we are tasked with saving the princess, though only a select few players knew the reasoning at the time; I don't know about you, but 4-year-old me had no love for reading, thus resulting in a swift trip to the trash for Mario's instruction booklet, along with the little detail given on why I should consider continuously venturing from left-screen towards the ever-expanding right-screen. LIMBO calls on this now inherent instinct in order to reward us with a glimpse of our goal towards the end of the game, only to be denied.
In Chapter 29, the Boy seemingly finds his way out of the industrial labyrinth of gears and saw blades to find himself back in the wilderness. Venturing rightward, the Boy finds his sister, her back turned to him, seemingly in prayer or at play. He eagerly runs to her, only to be turned around by another sneaky brain worm, bringing him back to the nameless factory he had just escaped. When the Boy finally makes his way back to the exit...it has disappeared. No wilderness, no exit, no sister. His princess is in another castle.
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