Honestly; you're n the wrong place; I believe. It's hard to tell from a single still, but from what I can figure:

The main image is a perspective top down camera on a 3D scene. If you always see from this angle the rest of the characters may have never been modeled reducing the work amount, but it certainly looks like 3D meshes and not pixel work.

Fog effect is a rather simple high-alpha particle effect. It's particles in order to make it dynamic, where an overlay would be far more static.

Shot effects are raycast draws on the path the shot takes (which is probably randomized); its a bit of tech art coding added onto the regular raycasting for the weapon.

The GUI is a regular GUI as you'd expect. This includes the target area, which is an overlayed circle with alpha on the GUI layer of the camera.

The minimap in the lower right corner appears to be an orthographic projection camera of the same scene using a clipping mask to render only a few objects rather than everything.

I'm sure that's not what you wanted to hear; but the art you're showing is 3D art and not 2D art.

I think I'll append to what I said. I -could- make this.

I'm trained in 3DS Max (3D modelling software) and Unity (3D game engine) more than enough to set it up.

Could have a rough prototype of the camera and game mechanics in a few days; finalized art and levels could take weeks, however. If you wanted more specifics; email or PM, please.