Nintendo

Nintendo Co., Ltd. (任天堂株式会社) is a Japanese multinational consumer electronics and software company headquartered in Kyoto, Japan. Nintendo is the world's largest video game company by revenue. Founded on September 23, 1889, by Fusajiro Yamauchi, it originally produced handmade hanafuda playing cards. By 1963, the company had tried several small niche businesses, such as cab services and love hotels.

Abandoning previous ventures in favor of toys in the 1960s, Nintendo then developed into a video game company in the 1970s, ultimately becoming one of the most influential in the industry and Japan's third most-valuable company with a market value of over $85 billion.

Mega Man
Mega Man, the first game in the Mega Man franchise, was first released to the Nintendo Entertainment System (NES for short, known as Family Computer/Famicom in Japan), later followed by Mega Man 2-6 and Wily & Right's RockBoard: That's Paradise.

Many Mega Man games were later released in other Nintendo consoles, including:
 * Mega Man 7, Rockman &amp; Forte, Mega Man's Soccer, and the first three games from the Mega Man X series in the Super Nintendo Entertainment System (SNES).
 * Five games from the original series and two from the Mega Man X series for Game Boy and Game Boy Color.
 * Mega Man 64 for Nintendo 64.
 * Mega Man Anniversary Collection, Mega Man X Collection, Mega Man X: Command Mission, and Mega Man Network Transmission for Nintendo GameCube.
 * All four games from the Mega Man Zero series, eight of the games in the Mega Man Battle Network series, and Mega Man & Bass for Game Boy Advance.
 * The three main games from the Mega Man Star Force series, the games in the Mega Man ZX series, Mega Man Zero Collection, Mega Man Battle Network 5: Double Team DS, and Rockman.EXE Operate Shooting Star for Nintendo DS.
 * Mega Man Legacy Collection for Nintendo 3DS, which was also re-released for Nintendo Switch.
 * And several Virtual Console releases for Wii, Wii U and Nintendo 3DS, most notably Mega Man 9 and Mega Man 10 for Wii.
 * Mega Man Legacy Collection 2, Mega Man 11, Mega Man X Legacy Collection, and Mega Man X Legacy Collection 2 for Nintendo Switch.

Outside the series, Mega Man also had cameo and guest appearances in several games released for Nintendo systems, including, but not limited, to Capcom Quiz: Hatena? no Daibouken (Game Boy), the Boktai games (Game Boy Advance and Nintendo DS), Tatsunoko vs. Capcom: Ultimate All-Stars (Wii), Project X Zone (Nintendo 3DS), and Super Smash Bros. for Nintendo 3DS / Wii U, the later having Mega Man as a playable character alongside popular Nintendo characters such as Mario, Donkey Kong, Link, Kirby, Pikachu, Samus Aran, Pit, and more.

Also, the Nintendo 3DS has a Mega Man StreetPass Puzzle, two themes, and badges in the Nintendo Badge Arcade.

Super Smash Bros (Nintendo 3DS / Wii U)
The following characters and elements appear in this installment of the series along with Mega Man.

Playable from the start

 * Villager- From the life-simulation series of games Animal Crossing. This is the first SSB game to include Villager.
 * Wii Fit Trainer- From the exercise oriented game Wii Fit. Her moves resemble various exercise poses, and while the default character is female, the male version can be selected as an alternate form.  This is the first SSB game to include Wii Fit Trainer.

Requires unlocking

 * Mr. Game & Watch- Original character made for Super Smash Bros series since Melee to represent the former line of Nintendo handhelds known as Game & Watch. Mr. Game & Watch made his SSB debut in Super Smash Bros Melee.  The character can be unlocked through:
 * 3DS- Completing Classic Mode 10 times or playing through 90 VS Matches. Afterwards, Mr. Game & Watch needs to be defeated on the Flat Zone 2 stage.
 * Wii U- Completing Classic Mode with 5 different characters on Intensity 2.0/Higher. Afterwards, Mr. Game & Watch needs to be defeated on the Flat Zone X stage.
 * Duck Hunt- Team character consisting of the dog, duck and an unseen player from the NES Light Zapper game Duck Hunt. This is the first SSB game to include the Duck Hunt.  The character can be unlocked through:
 * 3DS- Clearing Classic Mode with 8 different characters or playing through 110 VS Matches. Afterwards, Duck Hunt needs to be defeated on the Battlefield.
 * Wii U- KOing an opponent in Cruel Smash or playing through 100 VS Matches. Afterwards, Duck Hunt needs to be defeated on the Battlefield.
 * R.O.B. (Also known as Robotic Operating Buddy)- A peripheral sold with the Nintendo Entertainment System to make the set seem like a toy rather than a video game console due to the video game crash of 1983. Could be used to play NES games Gyromite and Stack-Up.  R.O.B. made his SSB debut in Super Smash Bros Brawl.  The character can be unlocked through:
 * 3DS- Collecting 200 different trophies or playing through 70 VS Matches. Afterwards, R.O.B. needs to be defeated on the PictoChat2 stage.
 * Wii U- Playing through 8 rounds of Crazy Order or playing through 60 VS Matches. Afterwards, R.O.B. needs to be defeated on the Wrecking Crew stage.