The following walkthrough is based on a tutorial I read online. I’d link to it but unfortunately I’ve lost the bookmark. Sorry ’bout dat. You’ll have to make do with what I can remember.
To start, I painted the miniatures with Vallejo Model Colour Bronze:
At this point they look like cheap and nasty toys. They start improving after a wash of Inscribe Turquoise though:
The next step is to drybrush the miniatures with a mid to light ‘leather brown’ kind of colour. If you overdo it, you can very lightly drybrush a bit of the bronze over the top to restore some of the highlights.
That leaves you with these:
I was very tempted to stop here but this was an experiment so I wanted to take the weathering to the extreme on at least a couple of the miniatures. I added streaks of verdigris and drybrushed lighter layers of turquoise onto some of the miniatures. The shields in the picture below are one step behind the figures:
After weathering the shields I realised that I’d gone a wee bit over the top with the verdigris…
Fortunately, the over-weathered miniatures were easy to fix with a wash of dark brown to dull the turquoise. I prefer to use thin layers of colour these days, but the resulting rough texture from all the drybrushing seems to works quite well in this case.
Here are the finished miniatures: