I would like to do markers, for teamates, objectives etc. which are basically just pieces of text or a symbol hovering over the thing in question’s head. That much I can do, what I can’t do however, is have the marker be visible through scenery and other object, any help?
Well…
This probably will require python:
You could use an overlay scene with the numbers. You’ll have to use python to set the numbers positions to be above your characters’ heads, and you’ll have to set the overlay camera’s position/orientation to be the same as the main scene’s camera’s.
Objects in the overlay scene will be rendered above everything else, so that should work for you.
-Sam
is there any other wya to do it?
yep,
as many as you want.
…but most are even more complex 
Can python not make things (in the same scene) be displayed on top of all other objects?
That’s a non programmer question, which translates to isn’t there a module which does all of the above for you. For which the answer would appear to be no. Nevertheless this sounds like an interesting challange, good luck and maybe when I’ve finished my current project, not to soon from the look of it I might have a go.
I am a programmer, I just don’t know all of pythons modules inside out and was wondering if one has an x-ray display function of some sort. One idea I had was that Blender does x-ray display in the viewport, could I toggle that on ingame somehow?