Kirby's Adventure (NES, 1993)

Unbeknownst to most people, the first game in the Kirby franchise of games was a massive critical failure.  Kirby's Dream Land on the Game Boy was an attempt by Adventures of Lolo creator HAL Laboratory to make a simple game to introduce kids to video games.  It was the story of the titular pink puffball who must reclaim the land's food from the totalitarian King DeDeDe.  Kirby could jump, fly, and inhale enemies to spit them back out at other enemies.  I can praise it for being simple fun and the graphics are quite nice for a Game Boy game, but it is not worthy on its own to be a Great Video Game.  Kirby's Adventure (1993) on the NES, on the other hand, is a different story.
In making a Kirby game for the NES, HAL must have realized that they were going to need more to play with to create a worthwhile home console experience, and what they came up with is a stroke of genius.  Now when Kirby inhales his foes, he can absorb their abilities.  There are over twenty copy abilities, ranging from fire-breathing to becoming a UFO.  Some of them are fairly common and can be used for a variety of fighting styles (such as sword, electric, or fire) and some of them are extremely rare (like backdrop, UFO and bomb).
There are eight main levels with sub-stages and a boss fight at the end.  Kirby starts on a "map" screen where he can roam freely and enter each stage through a door.  Also on this map screen are mini-games that offer extra lives or copy abilities.  There are some areas that are locked away and you must find a secret switch within one of the stages to unlock it.  Some of these switches are simply in a room that is hidden out of sight, and requires some exploration, but others require you to solve puzzles with copy abilities.  For one puzzle you will have to light a fuse and then quickly get into the cannon at the other end to launch yourself to the switch.  For another you will have to get the hammer ability in a different stage, bring it back to another, and use the hammer to break some underwater blocks to get to the room with the switch.
The story, this time around, goes that King DeDeDe is back, and he has stolen the Star Rod from the Fountain of Dreams, broken it into several pieces, and given it to his buddies.  The Star Rod is important because it allows the denizens of Dream Land to dream while they sleep.  Kirby battles his way to get the pieces back and replace the Star Rod in the Fountain, but as it turns out, DeDeDe was only trying not trying to hide it from Kirby, but another being known only as the Nightmare, who seeks to corrupt everyone's dreams.  Using the Star Rod, Kirby defeats it and restores peace in Dream Land.
This game represents NES action games at their finest.  In terms of visuals and sound, it has some of the brightest, most colorful, and best animated graphics, and some of the most memorable music on the NES.  The control is tight, the play mechanics are fully realized, and the possibilities for ways to play through each stage are virtually endless.  There would be another game on the Game Boy, Kirby's Dream Land 2, which would take the copy abilities from Kirby's Adventure and combine it with friends Kirby could ride.  On the SNES there would be Kirby Super Star and Kirby's Dream Land 3, and on the N64 came Kirby 64: The Crystal Shards, which is considered by many (myself included) to be the best Kirby game.  This first game was a big step in the right direction.