Lost Zem (ロストゼウム), also known as the Great Sable Hammer (巨の黒槌), was one of the Sept-Terrions and was the treasure governing Earth. In contrast to the Ark Rouge, which has dominion over souls, the Lost Zem has dominion over physical bodies.
Lost Zem was originally situated in the land of Erebos (Erebonia), where it was worshipped by a civilization now known as the Gnomes. After a cataclysmic battle with the Ark Rouge which destroyed both treasures, they fused into the Great One. The Lost Zem's lifeless body can be seen at the Nord Highlands.
The Chief of the Gnomes can command the Lost Zem to execute the Sacrament Program.
- 'Lost Zeum' is a portmanteau of 'lost' and 'seum' from 'museum' according to Toshihiro Kondo.
- Zem means 'earth' in Czech and Slovak.