"Voltaic resistance is best achieved by strapping frogs to your body. Their tough, thick, insulating hides will help protect you from any electrical encounters. Failing that, we recommend magic rings or something."
Voltaic resistance is important to have, as many enemies (Lord Dredmor included) deal it. It can be obtained from Potions of Voltaic Empowerment, copper accessories (belt, rings, etc.), the Cybertronic Amulet, and indeed, magic rings such as the Amber Ring of Unending Time.