WWII Walker 03

This may sound odd but I remembered the IJA's suicide AT lunge mine and how they were used by the IJA in the Gear Krieg tabletop game as mecha-issue weapons, like an anti-armour spear (or yari) for IJA mecha. Your Japanese light walker fits the bill if it has a secondary ranged weapon (like the Volkswalkers' arm-mounted weaponry) for suppressive fire while using a mecha-sized AT lunge mine as an anti-armour spear.