ID:265604
 
If I have a .bmp or something, would it cause less lag to build it with image() or have several overlays over one mob?
No.


Check out my ToolBox library: http://developer.byond.com/hub/DerDragon/ToolBox

It handles basicly what you're asking for here, automatically. You could at least take a look at the code to see how it's done. The proc you'd be interested in is "bigicon()".