Tried to post this the other day,don't know how 4chan works very well so my apologies in advance if this isn't formatted right or whatever.
Saw the trailer for Smash that's gonna get shown at E3, only got to see it once, opens up mid fight up an icy mountain, everyones fighting for a Smash Ball up at the top, you can see main characters fighting their respective villians for the most part, I saw Little Mac for a second too, and Mario tosses Bowser by the tail into a group of Melee/64 veterans and the Inklings (which were turning into squids trying to get up the mountain with ink, Link shoots a bomb arrow at them and knocks them off) and gets closer before Ice Climbers stomps on his head surprisingly and get close to the icy peak
Ridley snatches the Smash Ball and starts glowing, tail whips ice climbers down the mountain and Samus gets up after the Bowser toss, looks up, and charges a blast towards Ridley as he starts flying down.
Didn't see anything else after the trailer so may have only seen part, I'm assuming there will be a 3rd party reveal because it's E3 but I didn't see anything in what I saw.
If you have any specific questions about the trailer I'll try and describe more specifically - characters I know I saw were Mario, Peach, Bowser, Donkey Kong, Pikachu, Link, Little Mac, Marth, Samus, Ice Climbers, Ridley. I thought I saw Captain Falcon and Wario too but am not 100% about Wario, close to 100% about Falcon.
I know most people don't believe leaks, but I'll try and be transparent where I can, and I also don't want to make anything too obvious to be caught violating my NDA. About 25 other people were in the room with me watching so I think I have enough strength in numbers to tell you guys because I'm pumped.
Mario, Peach, Bowser, Donkey Kong, Pikachu, Link, Little Mac, Marth, Samus, Ice Climbers (returning veteran), I think Captain Falcon and Wario - new characters I saw was that squid inkling (I know it's from Splatoon but never played it) and Ridley at the end, and they highlighted Ice Climbers for some reason as if it was new