A clean Alpha Legion scheme meant for speed. The most important bit is the hue of the blue-green armour. Other paints or mixes may give different results.

It's divided in two workloads; airbrushing the armor and filling the details. Each can be done on different sessions and on different amounts of models. For instance, I do the airbrushing on 10 to 20 models at a time and then the hand painting on 5 models at a time.

For this scheme you'll need an airbrush and some skill with it!

1. Prime the model in red. For example Bloody Red spray.

Power armour

The main process is to do a zenithal highlight from the red to a bright silver and then glaze the blue over the whole armour. The blue will mix with whatever color is below it. It it covers the red they will mix into a nice dark color and if it covers the silver it will keep most of its blue hue and keep the metallic sheen of the silver.

1. Cover everything but the deepest parts of the model with Magnesium , spraying two thin coats at around 40º.
2. Highlight the armour with Silver , focusing in the upper parts and spraying one layer at around 20º and second layer directly from the top to reinforce the highest points.
3. (Optional; I don't bother with this for rank and file) Once the metallics are fully dry you can introduce additional shadows by glazing red. You can do this with either the airbrush or by hand. You can also reinforce lights with silver highlights.

I mix the blue-green from Liquitex Inks but others should work as long as they have the same properties. I use Muted Turquoise and Vivid Lime Green mixed 5:1 and that mix is then diluted with airbrush thinner in a 3:1 ratio of thinner to paint. Both inks are transparent, which is the most important property we are looking for. Alternatives like contrast style paints or washes are usually semi-opaque. Tamiya could be a good alternative but I don't have experience with it yet.

1. Glaze the blue-green tint color over the armour. Slow and steady letting each layer dry before applying the next one. 3 to 4 thin layers are usually what I do to get the color I'm after. The ink is so thin that some of the deepest recesses may not get covered and still show the primer. I actually want that since it creates chromatic shadows. If you don't, introduce some step before this glaze to cover those recesses (i.e. a wash)
2. Let is rest for a bit, a day at least. The ink is very fragile and even some pressure with your fingers may remove it. Once it fully cures it should be more resistant. Regardless, I apply a light coat of satin varnish.

The rest of the details

1. WIP