WOW! Thanks for the very detailed explanation!!! Kudos to you I'm using multisprite kernel indeed, but how can I manually define how many rows I want on the screen at visual batari basic code? I'm just trying to achieve a 'Breakout' clone here, with the same number of rows, same block sizes and same colors from the original game. And since it's a simetrical game, I'd like to use the whole screen, as you said it's possible by repetition or reflection of the playfield (in this case, the wall of bricks). Could you give an example on how to do such thing? And again, thank you for your kind support. Cheers, Roger