1. It would be amazing to have the Tetris blocks as a playable character in SSBU. Consider the following:

Here's a list of the various forms of Tetris pieces and their names that I reference in the petition 

For the standard walking form, the block would be in either the Cleveland Z, or Rhode Island Z, depending on which way the character is walking (Left and Right, respectively). 

For dash attacks, the character could rapidly change between forms , before settling back on its original Cleveland Z or Rhode Island Z form. 

For directional attacks, the Cleveland Z could turn into the Blue Ricky, and the Rhode Island Z could turn into the Orange Ricky. For a down attack, the character would turn into an upside-down Teewee to attack on both sides. An upward attack would be transforming into the hero piece (the vertical 4-line l piece.) 

When it comes to smash attacks, the down smash would be transforming into the smashboy form and coming down similarly to Kirby's down smash. Side smash attacks could be executed similarly to Ike or Luigi, or Pac-Man's side smash attacks, where you charge the character's smash attack, and it determines how far the player travels in the direction sideways. It would be interesting to place an outline of the Tetris piece on the spot where the charged attack will land, like many versions of Tetris offer before you drop a block in a specific spot. For the Up Smash attack, I really don't know what it would be, other than a recovery where the character spawns from the top of the map like it's a game of Tetris. Finally, the Neutral Smash attack could spawn in two random pieces, one on each side to land and deal damage.

The aerial attacks would be the same as the standard attacks, except for the neutral air attack (Nair) where the character would transform into the hero piece and spin in the air to deal damage.

The Final Smash Attack could just be Tetris blocks dropping from the sky, making a bunch of rows, and then the opponent is launched when a Tetris is formed.