This is what I imagined :
After the Smash logo appeared behind the swords and the flames, a nature plain can be seen, similar to the one where we meet Duck Hunt. Mario, Peach, Kirby, Yoshi, Pikachu, Olimar, Villager and Duck Hunt are walking merrily. Suddenly, the group is under a big shadow. They lift their head up and a big block can be seen falling on them. The block fall in the ground and Mario dodge it, the group dodge the other blocks that falls, and are identic to the Puzzle League/Panel de Pon blocks. Yoshi and Pikachu have a mind click, likely because they remember these blocks. They two dash forward, hitting the blocks falling, Kirby make a great jump and change him into the pink big block from the same game to give off the block in the land. Mario comes, Yoshi let him jump in his back, and Mario make a second jump to punch a star block. The block fall between two identic, that makes them diseappear. Mario continue to run, but see a very huge shadow and a giant block overhead him and dodge it just before it fall on the land. Peach beckons the big block and everyone is looking at this, it turns off to five heart blocks, that diseappear and release a light, that is flying for many seconds and after falls in the land and makes a flash. After the flash, a girl is floating in the air, and falls in the ground. The camera goes to her head, and she returns to reveal her. And here appears that message :
Lip
flowers it up
The gameplay video starts.
After the end, Olimar look at Lip making a trick that makes fairy dust fall in the ground and make growing three Pikmin. Olimar pick them and one of them clap Lip's hand.