I don't think this is even that far-fetched. Microsoft has shown some signs of an "if you can't beat em, join em" philosophy towards Nintendo this year, and this would be a mutually beneficial move.

Maybe not in Brawl, but in the sequel...?

 Like I said, I simply can't at this date.  I have two reasons that make me think that Halo DS could happen (note that though I do know a guy at Bungie neither of my reasons have specifically anything to do with Halo, just going off things I know for sure): one reason I just can't tell you at this date (and I'll be perfectly happy to come back and explain it when I can talk about it) and the other I simply don't want to talk about it.  I could talk about the second one since I'm not under an NDA about it but I really don't like starting rumors so for the moment I'll just keep that one.

I know it sounds like I'm just making stuff up, perhaps I am for all you know, but that's just how it is.  You don't have to believe in Halo DS based on what I've told you especially since I haven't really told you anything but based on what I know I believe it could happen. 

Master Chief does not even stand a chance against the peanut gun. It has jet propulsion. It's on like Diddy Kong!!!

@ Shido

Shouldn't link be holding the master sword in his left hand?

On topic: How would MC eat peanuts if he doesn't take off his helmet?

@twestern - You could be a politician with double speak like that! lol. I know Halo DS exists, I've seen the footage, so it's certainly in the realm of possibility. I hope your right. I'd love to see Halo DS, even though I don't own a DS or play Halo. Halo on the bus would be fantastic for all it's fans.

And I agree, although Brawl caters it's characters more to the Japanese, those 2 million extra sales in NA simply couldn't be ignored by Nintendo.

 Actually, the Halo DS that Cassamina (or however you spell it) showed everyone is never going to see the light of day.

Then Sephiroth would be in there too and pwn Master Chief :)

So you mean there's a new version of Halo DS in the works?!?! 

Is it just me or do certain characters feel out of place in SSB?

I think Mega Man would be more fitting than Snake... BenKenobi will hate me now. :(

Halo DS was never REALLY in the works. Rumor is, Microsoft commisioned a bunch of demos from various studios. But the title was never developed beyond that point. Cassie came upon either one of those demos, or a different, unsolicited demo.

MC would be a great Smash character for no other reason except that he would be the one which would most surprise people. Even more surprising than Snake. There's always Smash 4...