Let's say you want to compress a giant blob of NEUT into 1 pixel.
1. Pause the game
2. Draw some NEUT onto the screen
3. Open the console, and write the below commands:
!set x NEUT 100
!set y NEUT 100

Let's say you have a complex save and want to compress two not-before-used elements into a single space.
1. Pause the game
2. Draw both elements onto the screen
3. Open the console, and write the same commands as the above for every element you'd used.
For example, if you were trying to stack WOOD, GOO and ISOZ, then your commands would look like
!set x WOOD 100
!set y WOOD 100
!set x GOO 100
!set y GOO 100
!set x ISOZ 100
!set y ISOZ 100

Let's say you want to make a line of stacked particle
1. Pause the game
2. Draw parallel lines of both elements
(basically diagonal is safest direction wise but if you know beforehand if you want a horizontal or a vertical line, you can align your parallel lines to the direction you want)

3. If you want a horizontal line, then type in

!set y wood 100

where 100 can be replaced with any Y coordinate you desire (in the range from 0 to 384 starting from the top). Check debug view for a display of coordinates.

4. If however you want a vertical line, then type in

!set x wood 100

where 100 can be replaced with any X coordinate you desire (in the range from 0 to 612 starting from the top).


The commands will set the x as well as y coordinates of every NEUT particle to 100, thus placing them all into one square.
Note however, that more than 5 "regular" particles per coordinate pair will be turned into BHOL intentionally. The same thing happens for PHOT and other energy elements at around 15k stacking particles.