I do love dragons, and mecha, and ancient mechanical mysteries even more, so this was a real feast! :D Such intricate details, and imaginative/clear forms no less. The colors really bring forth these mythical beasts as well, though so bright wings... wonder if they could've appeared even more mythical/magical/ancient with a somewhat darker or jaded hue. I wonder how it would look with a little shading or texture too... not that it isn't enough as is.
Not to complain unnecessarily since this really is awesome but it does seem a little incomplete when some elements are colored and some aren't, as well. I imagine if the canvas was simply light gray, or something similarly ground-like, then that'd be enough. The white shines a bit. Becomes a focus point around the main motive.
Also holy shit you've sure poured in a heavy dose of time into some of these! Turned out great though.
-cd-