So I found this great looking little tutorial on how to do efficient and potentially infinite blood splatters: https://forum.yoyogames.com/index.php?threads/unlimited-blood-splats.1624/ However when I looked at the code the poster provided I knew something was missing. I don't understand how he achieves the effect of drawing a blood splatter only inside the wall, since the code doesn't check for anything related to that. Several users in that threa pointed out the same issue but it's not resolved there. It looks like this for me: <Image Link Removed - Malicious Domain Detected>/k6OaxQ As you can see some dots are a bit outside the wall. I acually like how this looks and I might even keep it but I'd really like to know how the effect in that tutorial was achieved. My code is the same as in the tutorial, which is obviously missing something. Thanks in advance!