Mechezarin

Mechezarin was a huge dragon owned by Durlag Trollkiller. We can assume that it was a Metallic Dragon, although this is not confirmed.

The dragon lived in a large room carved out underneath Durlag's Tower, along with other magical beast that Durlag kept. The massive beast eventually died, some time after Durlag passed. It's vast skeleton still rests deep underneath Durlag's Tower.

Appearances
In the game, Baldur's Gate: Tales of the Sword Coast, the player has to fight numerous Wyverns that are guarding the skeleton of Mechezarin, within Durlag's Tower.