Original sentence: The Demon Sorcerers are a group of ancient demons who once ruled the Earth in ancient times.They were all sealed in separate portals by the sorcerers using special immortalized items, although the portals can be re-opened using an item called the Pan-Ku Box which is essentially a puzzle box containing maps to the portals' locations
Edited sentence: The Demon Sorcerers are an group of ancient demons who once ruled the Earth in ancient times.They were all sealed in separate portals by the sorcerers using special immortalized items, although the portals can be re-opened using an item called the Pan Ku Box which is essentially a puzzle box containing maps to the portals' locations