Originally posted by Codetapper Almost every C64 game was assembler aswell - a few were a hybrid mix of BASIC and assembler (eg. Fruity/Players). AFAIK you couldn't get a C compiler on the C64.
I think you'll find that a few C64 games were actually written entirely in machine code. Largely from people learning how to program by using the monitor in freeze cartridges.
For anyone who doesn't know the difference, the INC command (increment) in 6510 is stored as the value 238 (EE). With an assembler, a line of your program would say, for example, "INC $D020" (which means 'add one to memory location D020'). When assembled, this would become "EE D0 20". To write in machine code means to write your program using only these types of numbers manually.