The Mace and Shield is an upgraded version of the EnergyBurn Mace, the Robotics' default melee weapon. It appears as a glowing barrier on the left arm, and a rocket powered hammer in the right hand. While blocking with a melee weapon normally causes an amount of damage to the attacker, the Mace and Shield deals double the regular damage.
A specific epic varient of the Mace and Shield is purchasable at level 32 from Dome City's Robotics Conquest Vendor, for 50 Conquest Tokens. Uncommon, rare, and other epic varients are rarely rewarded for high-end PvP and PvE mission completion.