In South Figaro, it blocks various passages and will probably kill Locke since he is fighting alone, and the Heavy Armor's inherent Protect greatly reduces the damage Locke deals to them. It is highly advised to avoid them by performing various other tasks, and to flee if the player encounters them by accident. However, the player can rarely steal an Iron Helmet from them, the most powerful helmet in the game at the time. If the player wishes to acquire an Iron Helmet, they should equip Locke with a Main Gauche, White Cape, Hermes Sandals, and Mythril Shield, then place him in the back row to ensure the best chance of surviving until Locke successfully steals the helmet. Even if Locke is killed, he is revived at the edge of town, and the player is free to return and try again.
In Narshe, they are much easier to face since the player has access to a full party and will be at a higher level. If Celes is in the party, the Heavy Armor will cast Magitek Barrier which grants Protect and Reflect on it. Thus, it is advised not to use magic against them, even though they have inherent Protect status. Instead, attacks that ignore defense work best, such as Sabin'sRaging Fist or Cyan'sFang.