 The team coded the game mostly in Forth with a few key routines written in assembler for speed . Forth was chosen since it was easier to use than assembler and more compact . This was important because the game had to fit into 128K of RAM . Many tools , techniques , and concepts used in the game were learned from other individuals in the Forth community . Some of the reference material included the " The Journal of Forth Application and Research " , <unk> conference proceedings , and " Forth Dimensions " magazine . 
