Mitchell is a secondary character from Kaza's Mate Gwenna. He's an antagonist who has shown up in several story arcs of the series.
Mitchell had been a poacher, guide and mercenary in the jungle for quite a while, and has had a number of encounters with Kaza. He was hired to guide Nerlana to the temple her father had used for his Serpent Cult. He took the gold in their treasure room as payment.
Later he was hired by the terrorist mastermind The Skull to follow Lady Catherine Maxwell, who had an artifact The Skull was after. He kept close tabs on her, following her even as she went to take a midnight swim. Lady Catherine ambushed him, and knocked him out with a club, and stole his rifle.
Later at the abandoned temple The Skull was using as a base of operations, Mitchell was present during Professor Morag's experiments with Solomon's Diamond, and when the artifact began destroying the temple. He, the Skull, and Morag tried escaping from the roof of the temple, finding only one single person helicopter. The Skull pulled a weapon on them and planned to take the vehicle, only to be stopped by Kaza. Mitchell offered to try and fly them all down, but the mini copter was destroyed by the crumbling temple. Luckily Gwenna and Alexi the zepplin engineer had commandeered the airship and Kaza and the rest were able to grab a tie down rope and hang one while they got away from the exploding temple.