As revealed in the episode "Desert Island Drought", Zig was born to a clan of extremely successful hunters who have found and killed many sea creatures throughout their lives.
At some point of his life, Zig got to the island and met Bernie.
Throughout the entire Season, Zig attempts to eat Marina and gets his attempts sabotaged by Sharko. He meets many new characters, like Jumbo the elephant and a shrimp powerful enough to defeat Sharko ("Little Shrimp Buddy"). At one point he visits a tribe of hyenas that look like him ("Goin' Home") and even befriends a small hyena.
At the beginning of season 2, Zig now has an edge in his hunt to eat Marina as the mermaid, in the first episode of the season, moves into a house on the beach of the desert island (however, he still has the same old problem with getting past Sharko). Over the course of the season, Zig has been shown in a much more anti-heroic light when he's had to defend Marina from others who want her, such as his three younger cousins in "A Relative Problem", who are just as hungry for the mermaid as Zig is, if not more so. However, in one episode, titled "Catch You on the Rewind", Zig actually succeeds in eating Marina, though this was undone by Sharko with the help of Hades' universal remote.
Even though Zig is a hyena, he doesn't particularly look like any of the four real-life hyena species - he has no visible neck, with small, sharp ears, red eyes closely placed to each other, a short, paintbrush-like tail, light brown fur, a mane and a prolonged snout with large teeth, akin to that of a human (at some moments he is shown with more fitting carnivorous teeth). As a result, many viewers mistake him for another animal. Zig is a hyena of short stature, and is scrawny; he has long, thin arms and short legs.
Zig is an always hungry, embittered hyena, somewhat similar to a mindless predator in his obsession with eating Marina. However, he was much smarter than the creatures living next to him, although dumber in comparison to his partner Bernie.
Zig is a cunning, but somewhat naive hyena who is willing to use anything to help him in his goal to eat Marina. Unfortunately, he has deceived many animals in order to do that, and, due to this, none of them will help him and will usually mock him.
Zig is also particularly charismatic and charming, even making a woman fall with love in him in "Loony Cruise".
It is possible that Zig might be mentally ill from his hunger and starvation, which has been implied in the endings of "Fishy Story" and "Caution, Genius at Work!", where he looks at Bernie with crazy eyes and foamy mouth.
Powers and Abilities
As been mentioned in the infobox, Zig is pretty intelligent (though not as intelligent as Bernie), capable of building contraptions himself, and is charming enough to seem friendly to Marina or to charm a woman ("Loony Cruise"). While he isn't strong as Sharko, he is capable defeating him strategically as long as Sharko does not capture him (as seen in "The Horribly Hungry Hyena", where he drops his engagement ring into the sea, thus trapping him in a fishing vessel net). Zig is also very agile and capable of riding motorized vehicles and sea vessels ("Cruising", "The Slick", "Horribly Hungry Hyena").
However, he has two major disadvantages. He is not strong enough to defeat the obviously stronger, brutish Sharko and has moments of idiocy (ex. in "Save the Hyena", when he captures Marina by pretending to drown, she rants at him for willingly endangering himself. He laughs at it instead of knocking her out, allowing her to take a nearby frying pan and smash him in the head).