Hi, I'm seeking help on how to create atmospheric smoke/haze. Is there somewhere I could get a specific brush for that or would you recommend using a blending layer and stock brushes? I know people use the standard airbrush to pull and push objects farther/closer but I'm looking for a solution with a bit more substance. I suppose I could probably photobash some smoke or haze into my images as a last ditch effort but that's far from ideal. If there already is a topic that has dealt with the matter please point me to it and feel free to delete my post.

You could try painting with 'fog'. Filter -> Start GMIC-Qt then select the Render group in the GMIC window and choose Plasma. This gives you multicoloured 'fog' so ignore the colours and concentrate on the texture and patterns. Adjust the sliders to see if you get something you like. Then press OK and you have your paint layer filled with multicolored fog then you do Filter -> Adjust -> Desaturate to get grey fog. You can blur the fog a bit if you like. You can add a colour cast with Filter -> Adjust -> Color Balance.

Then you add a Transparency mask to it and fill the transparency with black to make it totally transparent (invisible). Then you use a brush to paint white at various levels of brush opacity onto the transparency mask so that you reveal/paint with fog/smoke.

I've used this method in the past for fog and it looked quite good (to me) but I'm not sure about smoke which can have many different types of textures and colours. You could give it a try with various brushes to see if it works for you.

Oh man, this is some next level wizardry. Thanks to your instructions it was easy to set up. I'll definitely give this a go! Cheers!