This is the Warden Helm from the Game "For Honor". I designed this in Fusion 360 and 3D-Coat. The helm is sized to sit a male adult.
Note : There is a hook for the side of the helm that is not in the pictures.
From Wikia:
"The Wardens are powerful, noble warriors dedicated to the defense of their land and their people. Striking a balance between defense and offense, wardens wear partial plate armor with chainmail and leather. Wardens wield massive two-handed longswords for slashing enemies and blocking attacks. Trained to be proud, loyal, and brilliant diplomats, the Wardens are expected to embody the highest values of Knighthood. Many set out to achieve this, few do."
