One of the first games that had such a level was Kid Icarus, in which you spent the entire game as a land-locked flightless angel as you amassed tools for fighting medusa. At the very end of the game, you finally took flight and the game became very different for its final level. Of course, this approach of saving the best for last can also backfire horribly, as in Battletoads vs. Double Dragon's final stage in which the game suddenly switches from sidescrolling brawler to intergalactic shooter (and if you die, no more continues!). When what you think is a great finale is actually a horrible departure from enjoyable gameplay, it can demolish the entire experience. Maybe that's why the great Resident Evil 4 put its best level right in the beginning, as you face off against an entire village of homicidal maniacs. Sometimes putting the best foot forward propels you through the rest of the game.
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