It moves the sprite based on its ID. A sprite ID is a number that usually appears first in the command and it indicates what sprite you want. For example: ACLS SPSET 0,1 'Makes a sprite with ID 0 SPSET 1,2 'ID 1 WHILE 1 SPOFS 0,MAINCNT MOD 400,119+(SIN(MAINCNT MOD 360)*10) SPOFS 1,MAINCNT MOD 400,119+(COS(MAINCNT MOD 360)*10) VSYNC WEND Cool effect!