The first appearance of the lost hero is on the V12 series, that strongest shark Cobalt. It has trendemous strength, it also have some skills which really amazing, making it a lost hero. The colour of that shark is blue, it is the brother of Master Blue. This should be revealant, this shark can revive itself after health reaches hero, works more better with Survivor!
This animal led the 3 escaped animals got out of their prison, which make them an escaped animals, and Cobalt himself is the boss animal of V12, while the card has been released at that version too.