Caw

Core was a big, golden bird who could speak and worked with Baltazar on Baltazar's ship. Core was living metal from Pheros and ate gold, and Baltazar promised him all the gold he could eat. Core had a son called Squawk. Core had turned on Baltazar and sent him to the "prison planet" Volag-Noc, but Core worked with him again after tricking The 10th Doctor and Martha Jones to find the Infinite for them. Core's fate was sealed when he was shot by Gurney (the fake Gonever of the Prison Planet). Core was shot right in the fusion chamber, and Core runs on Gold Fusion too stay alive for years! That is what Baltazar promised to Core