Zern is a dragon who was known to have assisted the Ogre Raiders in the Ogre Wars. Zern is said to have torn down one of the walls of Azmar Castle to allow Ogre Raiders to get in. Zern fought at the Battle of Ogre Island. It is said that in that battle, Zern killed and ate the Warlord Karleg of Azmar. Dragon Hill on Ogre Island is named after Zern.

Zern is believed to be very old. At the Battle of Ogre Island he was seen clutching a magic staff, the head of which was pulsing with a strange blue light. The legendary magic merchant Thoreg, who was present at the battle, said that he recognized the staff as Grivenek's Staff, a unique magic item created by the Elder Gods and given by them to the gnome wizard Grivenek in the Elder Days.

Grivenek lost the staff when a large dragon landed in the market place of Port Town, took the staff from Grivenek, then flew off. Even though this incident happened in the early days of the First Age, it is believed that this dragon was Zern.

Zern has been described (by the gnome wizard Grivenek) as being fifty feet tall and dark green or black in color.

Zern was once seen flying over Worfin Island by the elf Thaero, High Ranger of Azmar.