Mega Man 2

Mega Man 2, known as Rockman 2: Dr. Wily no Nazo (ロックマン 2: Dr.ワイリーの謎) in Japan, is the second game of the Mega Man series and is considered by many fans the best Mega Man game for the NES.

Overview
Dr. Wily is back, and now he's created eight new Robot Masters to defeat Mega Man. Mega Man will have to stop Dr. Wily's robots and bring him to justice again.

There is no difficult select in the Japanese version of the game. There is a normal mode and a difficult mode in the English versions, which Difficult is the original Japanese mode and Normal is an easier mode in which Mega Man's attacks causes twice damage. The difficult select is only available in the American NES and mobile phone ports of the game.

Story
From the game:

"In the year 200X, a super robot named Mega Man was created. Dr. Light created Mega Man to stop the evil desires of Dr. Wily. However, after his defeat, Dr. Wily created eight of his own robots to counter Mega Man."

Trivia

 * This is Keiji Inafune's favorite Mega Man game.
 * This is the first Mega Man game that shows the map of Wily Castle.
 * This is the first Mega Man game to have Dr. Wily create his own set of Robot Masters, instead of using someone else's.
 * This is the first Mega Man game to have the "Teleport System" when encountering the Robot Masters again.
 * This is the first Mega Man game to have Energy Tanks, although the player could only carry four, instead of nine as in later installments.


 * Like the first game, using a Game Genie on Mega Man 2 will cause the music to be riddled with quirks and odd sounds.
 * Quick Man's stage is taken from this game and is used as Dr. Wily's fortress stage in the Game Gear Mega Man game.
 * Also, Shadow Devil's stage in Mega Man X5 and QuickMan.EXE's stage in MegaMan Network Transmission are similar to Quick Man's stage.
 * Many ideas that were not used in the original Mega Man game, due to cart size limitations, were recycled for Mega Man 2.
 * This is the only Mega Man game so far to have a robot master that is weak to his own weapon.