when gf clicked
move right :: motion
move left :: motion
while tape != 0 :: cstart control
increase :: operators
decrease :: operators
:: cend
execute :: control

forever - repeat (99999999999999999...)
go to x:() y:() - set x to (), set y to ()
move () steps - lot of code I can't post here but definitely possible
change [v] by () - set [v] to (thing) + ()
() * () - use () + () repeatedly
if then else:

set [else v] to [0]
if <thing> then
set [else v] to [1]
end
if <(else :: variables) = [0]> then
...
end

NickyNouse wrote:

Forever and repeat () would both be out, the only thing you technically need is repeat until
the subtract block is gone, you can do ((x)+((-1) * (x)))
likewise, a good portion of the functions in the ([ v] of ()) operator block can be achieved with if-else and a lot of basic arithmetic blocks
custom blocks are probably out, everything you can do with a custom block can be achieved with a broadcast one way or another

DigiTechs wrote:

Due to how Scratch is structured, you don't even need ‘repeat until’; broadcast ‘tail calling’ would work fine.

DigiTechs wrote:

You don't even need multiply, really; just use repeated adding. Division might be a mandatory though (unless you want to work in 1 remainder 2 land) and modulus can just be repeated subtraction until x is less than your divisor (i.e. 1 remainder 2 land).

() - () // use join[-](number)
() * () // REQUIRED
() / () // https://scratch.mit.edu/discuss/post/1955358/
() and () // https://scratch.mit.edu/discuss/post/1955054/
() Mod () // use / and floor
() + () // REQUIRED
() < () // REQUIRED
() = () // REQUIRED
() > () // use not < and not =
() or () // use not<not<> and not<>>
Answer // REQUIRED
Backdrop # // REQUIRED
If on Edge, Bounce // use touching edge and rotate 180
Broadcast ()  // REQUIRED
Change () Effect by () // keep track of effect value with variable
Change Pen Color by () // keep track of color with variable and do hsl calculation
Change Pen Shade by () // same
Change Pen Size by () // keep track of pen size
Change Size by () // keep track of size
Change Tempo by () // keep track of tempo
Change () by () // use set [thing] to ((thing)+(...))
Change Volume by () // keep track of volume
Change X by () // keep track of position
Change Y by () // same
Clear // REQUIRED
Color () is Touching ()? // REQUIRED
Delete ( v) of [ v] // REQUIRED
Go to Front // use move back (-9999)
[ v] of ()::operators // REQUIRED
Join ()() // REQUIRED
list reporter::list // REQUIRED
Costume # // REQUIRED
Create Clone of () // use stamp / lists
Delete This Clone // same
Distance to () // calculate yourself using () of () sensor
Ask () and Wait // REQUIRED
Broadcast () and Wait // set a variable at the end of your broadcast and wait for it
Forever // use repeat until <1=1>
End
If () // use if, then, else
End
If () // https://scratch.mit.edu/discuss/post/1955002/
Else
End
Play Sound () Until Done // REQUIRED
Repeat () // use repeat until + variable
End
Stop [ v] // REQUIRED
Repeat Until () // REQUIRED
End
Wait Until () // use repeat until
Play Drum () for () Beats // REQUIRED
Clear // REQUIRED
Move () Steps // use set x/y and sin/cos
[ v] of [ v]::sensing // REQUIRED
Item () of () // REQUIRED
Username // REQUIRED
Glide () Secs to X: () Y: () // use loop
Go Back () Layers // REQUIRED
Go to () // use () of () or mouse x/y
Go to X: () Y: () // REQUIRED
Direction // keep track yourself
Point in Direction () // REQUIRED
Hide // REQUIRED
Hide List () // REQUIRED
Hide Variable () // REQUIRED
Insert () at () of () // REQUIRED
Key () Pressed? // REQUIRED
Letter () of () // REQUIRED
Length of [ v]::list // REQUIRED
() Contains () // search yourself with loop
Switch Costume to () // REQUIRED
Set Instrument to () // REQUIRED
Mouse Down? // REQUIRED
Mouse X // REQUIRED
Mouse Y // REQUIRED
Next Costume // use switch costume
Next Backdrop // use switch backdrop
Not () // https://scratch.mit.edu/discuss/post/1954949/
Play Note () for () Beats // REQUIRED
Set Pen Color to [#ffffff]  // REQUIRED
Set Pen Size to () // REQUIRED
Play Drum () for () Beats // REQUIRED
Play Sound () // use play until done with broadcast
Point Towards () // point towards atan (x/y) of (thing)
Pen Down // REQUIRED
Pen Up // REQUIRED
Pick Random () to () // make own PRNG?
variable reporter::variables // REQUIRED
Rest for () Beats // use repeat until + days since 2000
Round () // floor/ceil
Say ()  // REQUIRED
Say () for () Secs // say [thing], wait using repeat until, say []
Size // keep track yourself
Backdrop Name // keep track yourself
Video () on () // REQUIRED
Set () Effect to () // REQUIRED
Replace Item () of () With () // use insert/delete
Set Pen Color to () // calculate hsl yourself
Set Pen Shade to () // same
Set Rotation Style () // REQUIRED
Set Size to ()% // REQUIRED
Set Tempo to () bpm // REQUIRED
Set () to () // REQUIRED
Turn Video () // REQUIRED
Set Video Transparency to ()% // REQUIRED
Set Volume to ()% // REQUIRED
Show // REQUIRED
Show List () // REQUIRED
Show Variable () // REQUIRED
Loudness // REQUIRED
Stamp // REQUIRED
Switch Backdrop to () // REQUIRED
Switch Backdrop to () and Wait // repeat until backdrop changed again
Stop All Sounds // REQUIRED
Length of ()::operators // loop as per theonlygusti
Tempo // keep track yourself
Think () // REQUIRED
Think () for () Secs // think [thing], repeat until to wait, think []
Current () // use days since 2000
Timer // use days since 2000 and offset variable
Reset Timer // REQUIRED (for hat block)
Days Since 2000 // REQUIRED
Touching ()? // REQUIRED
Touching Color ()? // REQUIRED
Turn cw () Degrees // use point towards
Turn ccw () Degrees // use point towards
Volume // keep track yourself
Wait () Secs // use repeat until + days since 2000
When This Sprite Clicked // REQUIRED
When I Start as a Clone // use stamps/lists
When Green Flag Clicked // REQUIRED
When I Receive () // REQUIRED
When () Key Pressed // REQUIRED
When Backdrop Switches to () // REQUIRED
When () > () // REQUIRED
X Position // keep track yourself
Set X to () // use go to
Y Position // keep track yourself
Set Y to () // use go to

MegaApuTurkUltra wrote:

Let me try to precisely define “Fewest amount of blocks technically needed to use Scratch”

Fewest amount of blocks needed to exactly replicate the functionality of any normal Scratch project

-snip-
There are probably still more that can be snipped out of this

bobbybee wrote:

SUBLEQ

((x) + ((y) * (-1)))

• , and replace item () of with (), if<>{} else{} (or if<>{} and stop ), and =. Loops can be achived by recursion on custom blocks, or broadcasts. (but with broadcasts, we'd need variables, which can be emulated with the list blocks we allow ourselves to use). Your states would be in the form:
  (edit: I can't get the formatting to play nice, so just quote this to see what I actually wrote)
  
  

  define state1 (index)
  if <(item (index) of [tape v]) = [desired symbol]>
     replace item (index) of [tape v] with [new symbol]
     state2 ((index) + (1))
  else
    if <(item (index) of [tape v]) = [another symbol]>
      replace item (index) of [tape v] with [another new symbol]
      state3 ((index) - (1))
    else
      ...
    end
  end

  
  You'd also need the green flag block to start this off.
  
  I suppose at some point you're going to want to write something to the screen: then you'd just need go to and stamp, to print black pixels to the screen (make the costume a black pixel), and clear to wipe it. Alternatively, costumes for every colour pixel you want to use, then stamp. Don't need clear now as with a white pixel you can overwrite everything.
  
  Then if you want some user input, (mouse x), (mouse y) and <mouse down?> will allow you to take mouse input. You can draw a virtual keyboard, and detect when it's clicked, so that gives you keyboard input too.
  
  You might want to add in the blocks for cloud storage, camera detection, the lego motor and pico board plugins, to be able to do everything scratch can. Or course, extremely slowly.

MegaApuTurkUltra wrote:

In that case

(x position)
(y position)
(direction)

if <condition::sensing> then
    
else 
  do stuff :: sound
end

scratchisthebest wrote:

You can get rid of “not” because of this:

if <condition::sensing> then
    
else 
  do stuff :: sound
end

PullJosh wrote:

scratchisthebest wrote:

You can get rid of “not” because of this:

if <condition::sensing> then
    
else 
  do stuff :: sound
end

Does this work in all situations? I can't think of any specific examples, but it seems like a “not” included inside of a massive tree of logic gates wouldn't be able to re replicated with this…