Blue
A variant of Old English Game (Gallus gallus domesticus)
Representative Old English Gamephoto — a dedicated image of this exact morph isn't available yet.
Blue-feathered OEG (e.g. Blue-Breasted Red or self Blue) from the blue dilution gene, giving soft slate tones.
Keeper tips for this variant
Blue won't breed 100% true — expect black and splash in the clutch, and as always keep rival OEG cocks permanently separated.