I can't think of one right now, but when has Nintendo as a first party ever developed a Rate 'M' game?

By 'first party' do you mean the EAD teams? 

Well, basically, not including even the 2nd parties. Maybe I don't know my video game history enough, but I can't think of one right now. The only one I can think of is Project H.A.M.M.E.R., but that's cancelled.

Back in the day they had Metroid and Punch Out!! that I can think of. Both had themes that appealed to older crowds without falling into the gore or explicit category. Even duck hunt you could say was adult with a touch of kiddy. After all, you were killing ducks, and could even see them falling dead to the ground.

imho even SMB was adult themed in its inception, and so was Zelda. Level 9 of Zelda gave me the creeps as a kid. And when you die the black and red colors, not for the faint of heart at the time. (I found)

I also find that Zelda II was geard towards older players personally. The themes, colors and challenge are all not really well suited for kids.

i've learned a lot from this thread... apparently "mature" content is separate from "quality" content, nintendo is apparently one of the rare companies still producing this "quality" content and those who appreciate mature content in reality are immature and appreciate that content because they desire to grow up... pretty interesting

In all honesty, I agree that Nintendo push out a lot of quality games that is arguably mature themed by definition, but there's a reason why Nintendo want GTA on their system, a Rated 'M' game by ESRB's definition. That's obviously a market Nintendo hasn't quite captured yet. It's also a type of genre they opposed in the past, and has not had much of history developing.

Isn't it a great thing to be enlightened though?

Speaking as Spurgeon Ryan, " I say Nintendo needs to work on graphics like they did back in the days of my beloved N64. New IPs are a most because I demand bloody, shooters in my games.I really cannot stand kirby either please make something new.

2nd party refers to a 3rd party game that Nintendo publishes (think Geist from n-Space).  Stuff like Perfect Dark and Conker's Bad Fur Day would still be considered first party.  But obviously they are not part of the Japanese EAD teams.   Same with Disaster: Day Of Crisis being developed my Monolith Soft.  It's first party but not from the EAD teams.  

Project H.A.M.M.E.R. was being developed by Nintendo Software Technology; one of their US development teams.  And because it was canceled, we have no idea what the ESRB would have rated it though having played the early build at E3 I suspect no higher than 'T'.

What are you talking about?? Rare, Silicon Knights, those studios are what we called and have always called 2nd party studios, until they are completely absorbed by Nintendo.

So no, he was right, those were 2nd party games.

----------------------------------------- EDIT -----------------------------------------

I have to clarify this... Apparently there is no such thing as a 2nd party developer... it's a misnomer and always has been, apparently.

http://en.wikipedia.org/wiki/Video_game_development_party#Second-party_developer
"It is colloquially used in reference to a type of first or third-party developer that specializes in development for a particular platform."

But since Rare was never acquired by Nintendo, it was still a 3rd party developer:

"First-party developers may either use the name of the company itself (like Nintendo), have a specific division name (like Sony's Polyphony Digital), or have formerly been an independent studio before being acquired by the console manufacturer, such as Rare or Naughty Dog.^[1]"

The mention of Rare here is in the case of Microsoft, as Nintendo never fully acquired Rare. 

So Perfect Dark would, by the same colloquialism, be called a 2nd party game during the time of the N64, during which time Rare would colloquially be called a 2nd party developer. If Geist is 2nd party (by colloquialism), then so was Perfect Dark for the N64.