Lightning based equipment is mainly found in Legaia 2: Duel Saga. Legend of Legaia's only Lightning based accessories are the Thunder Egg and Madlight Jewel. In Duel Saga, Lightning equipment ranges from weapons that add the Lightning element to attacks, to armor that reduces damage against Lightning, to collectibles that have to do with the element itself.
There are Arts in both Legend of Legaia and Legaia 2: Duel Saga that utilize the element of Lightning. All of Gala's physical attacks hit with the Lightning element considered. In Legaia 2: Duel Saga, Sharon's attacks are based on the Lightning element. Maya also uses Lightning magic, which are the following: Thunderhead, Skysplitter, and Raging Sky.
In Legend of Legaia, Lightning summon spells include the most powerful of the regular Seru summons. Theeder is the earliest Lightning Seru that can be obtained and summoned, followed by Viguro and Gilium. The most powerful summon spell is Ozma's Voltagor. The magic effect of Lightning element summons is a reduction of the targeted enemy's INT stat.