The Thunder Book I (雷の奥義書1, Rai no ōugisho 1, lit. "Occult Book of Thunder I") is an item found in Legend of Legaia. It is a book of Hyper Arts for Ozma that allows Gala to execute the Thunder Punch technique.
|Thunder Book I|
|Effect||Teaches Ozma Thunder Punch.|
|Find At||Zeto's Dungeon|
- It is necessary to use the Thunder Book I in order to obtain Ozma's summon spell at the Genesis Tree in East Voz Forest after returning from the Seru-kai.
- Thunder Book I is the only Book of Hyper Arts that can be missed permanently. If it is not picked up from the treasure chest in Zeto's Dungeon before defeating Zeto, then the book will be forever unobtainable as access to Zeto's Dungeon afterward is impossible.