Hi all! I'm coding a multiplayer game with server verification and the first thing you need when doing so, is a deterministic environment. And my issue is that velocity seems not to be even remotely reliable... I made a sandbox to illustrate my issue : http://phaser.io/sandbox/edit/vLcJZUDX You can see that from frame to frame, the delta x (in px/s) is really different. I could set the x and y myself (without using velocity), but then I would loose the collision detection, which I want to use, of course. Am I using velocity wrong? Is my sandbox poorly done? Thanks a lot guys!