Tetris, you all know it, you know it's on everything ever. It's also on WonderSwan.

This verison is notable for being one of the first official Tetris game to follow the Tetris Guideline that's still in use today over 20 years later, alongside Tetris Worlds.

Unfortunately this version is also notable for not clearing lines properly.

When it comes to making Tetris games, when you make a full line, the game is supposed to remove it and make the rest of the stack above it fall one row. In practice, the easiest way to achieve this is by copying the row above the full line into the full line, then the row above that one into it, and you keep going until you reach the top of the playing field. So for example, if you fill the 4th row from the floor, row 5 gets copied to row 4, row 6 gets copied to row 5, row 7 gets copied to row 6, and so on. However, when you do this, you have to remember to then replace the highest row of the field with an empty row, otherwise you end up with the stack falling as usual, but whatever was in that row ends up copied into the row below, and nothing happends to the highest row, and it ends up duplicated. This is exactly what happens in WonderSwan Tetris: the field is actually 24 rows high (4 rows are invisible above where pieces appear), so row 24 gets copied down on every line clear, although the devs probably didn't notice because they never realised you could actually place pieces that high.

As this game follows the Tetris Guideline, the pieces in the game rotate according to the standard Super Rotation System. This is good because there are a few situations where we can force the piece to move two cells up. The ones I use the most in the run look like this:

            [][][]
  [][]          []
  []#### ->     ####
  []####        ####

            [][]
    []        [][]
  [][]            
  []#### ->     ####
    ####        ####

 
              [][][]
  [][]        []
####[]   -> ####
####[]      ####

                [][]
  []          [][]
  [][]          
####[]   -> ####
####        ####

Those moves allow us to place pieces into row 24 by building a field like this and making L/J pieces climp to the top:

()()()        ()()()
()  ^          ^  ()
##  ^          ^  ##
##()()        ()()##
####()        ()####
##  ()        ()  ##

This fills 6 of the 10 cells of row 24, and we can fill the last 4 by building some support and finagling a long bar to kick itself all the way up there. I ended up using this sequence of moves to get it where I needed.

Row 24 is now full, but it won't actually clear right away. The game in fact only checks for line clears on rows that are actually visible. This is why we build a Tetris well at the start of the run, so that we can then clear 4 lines and copy our row 24 contents into the visible field.

Unfortunately, the top of the visible field is also where our pieces appear, and if they appear in a wall, it's usually game over. It does end up being a problem when building to get pieces up high, but fortunately for us, the game straight up forgets to check whether our piece spawn location is blocked right after clearing a line for whatever reason, so once our line from row 24 gets copied into the visible field, that line gets cleared every time we place a piece so we don't have to worry about being blocked anymore, and we can let the game finish.

This run can most likely be improved of course. While you can't manipulate the piece sequence once you've started like you can in NES Tetris, you can still get a different piece sequence by waiting on the title screen. I took the first piece sequence I could and worked with it until i found something that worked, but I did end up discarding a few pieces on the stack. There could be either a better sequence or a better strategy that could lead to a faster time.

Another thing to note is that this is trying to end the inputs as early as possible, rather than get the fastest in-game time. You could do a variant of this run that aims for the fastest in-game 40 lines time, or do other things like bring that to Marathon, or even show the score completely freaking out by using this to clear 5 lines at once.

Ultimately though, like my previous submission, I mostly wanted to have fun by taking a silly premise in a Tetris game to make a tool-assisted run for. Happy April fools!

Darkman425: Something tells me your attic is a bit full.

Darkman425: This one was actually pretty fun to watch. The glitches were also pretty well explained and work when finding the minimal inputs needed to complete the 40 Lines mode. While there might be indeed a better possible piece RNG seed that seems like something that would be better suited for an improvement in the future due to the amount of work needed to check that.

Kids gotta learn about how weird the SRS works in practice someday. Accepting to Standard.

Spikestuff: Processing...