This subspecies of Metal Ghost is said to have changed after having amassed extensive records on the element of thunder. Though they're thought to be ferocious due to them being of the thunder element, they are calm and speak with composure which causes some Summoners to walk away in pure bewilderment. The element of thunder is much stronger in them than in normal Metal Ghosts, and it's said that when fused to other thunder types they provide loads more experience as well.
Thunder Ghosts are best used as an ingredient for fusion, providing a base of 1,506 XP. When fused with Thunder element units, it grants 2,259 XP, not including Great Success (x1.5) or Super Success (x2). The Thunder Ghosts only sell for 1,000 Zel each.