The Buried Sea introduces players to a new type of inventory slot called a Power Source which is used for new equipment available in the expansion, known as an Energeian Power Source. Energeian Power Sources are similar to a magical battery and come in a variety of types such as: fire, cold and light. Within the expansion, a new type of armor is available called Energeiac Armor which, while relatively basic by itself and suitable for a player to wear out in Norrath, is built to be powered by an Energeian Power Source and comes into its full power when that is the case. For example, when a fire-magic power source is equipped the armor gains offensive stats, increasing stamina, strength, and endurance but weakens the wearers ability to resist cold-based attacks. Power sources can be changed out at any time, allowing the player to quickly customize their entire armor set to best match the conditions they are fighting in.