You run a GOOL instruction (I-instruction) or call another subroutine by simply writing its name, then the list of parameters, enclosed in parenthesis, separated by commas: nop() // no operation playanim(0, 0, .5s) // play frame 0 of animation 0 for half a second MySub(true) // "MySub" is declared at some point The full list of built-in I-instructions is described in a later section of this manual.