Block shatter subroutine. This creates 4 block pieces and plays the shatter sound effect, but it does not actually destroy the block (use $00BEB0 for that). If A is 00 when calling this, the block pieces will be brown, while if A is a nonzero number, they will flash palettes. It uses $98-$9B to set the XY position. Note that this should be called with the data bank set to 02.