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NHL'94 for Sega Genesis was released by Electronic Arts, more well known as EA. EA has been putting hockey games on the market since around 1992, when the first NHL game came out for Sega Genesis (called EA Hockey). This first release was simple, but had the makings of a great hockey game. Key features were the ability to pick a fight after any stoppage of play, and using the slow goalies and players to your advantage. There was also a European verision of this game known as "Hockey 91", though I haven't had a chance to play this version yet.
Then NHL'93 came out the following year, and of course with some new perks. Key features in this game were the ability to now control your goalie, blood on the ice, line changes, and improved speed of players and goalies. You couldn't pick a fight much anymore, but don't be suprised when Alexander Mogilny decides to fight Chris Chelios and gets knocked out in 1 punch.
With 2 hockey games under their belt, EA released a masterpiece: NHL'94. A game that is still played and obsessed over by hockey lovers since the time it came out. Key features in this game are the infamous "one-timer", better all-around control of players, breaking the glass, the random kid in the stands that walks to the glass, and being able to save your records. They did remove fighting and blood which is a loss we have to deal with, but the game still ranks as the best NHL game to date in my opinion. Of course, this can be debated and I'm sure there's plenty of hockey lovers who disagree with me.
The NHL games that EA released after this weren't as good. Some will argue that NHL'95 was just as good, if not better. But I feel NHL'95 was too fast, and too easy to score on the goalies.
EA is still making this series annually. Their NHL'06 release ironically includes the one and only NHL'94 on it, though the real players and team names aren't in the game.