A Zombie Elephant is the product of an elephant succumbing to t-Virus infection. Currently, only one Zombie Elephant has been known to have existed, that being a Raccoon Zoo attraction named Oscar.
In the past, Oscar was the star attraction of the Raccoon Zoo and many people gathered to see most of his performances at the Elephant Stage. After the t-Virus spread throughout the city, Oscar became infected along with the rest of the animals. Now the zombie elephant rampaged through the zoo and surrounding streets, attacking anything with impunity.
During the earliest days of the Raccoon City Incident, a band of survivors attempted to cross through the zoo to reach an evacuation point on the other side. The elephant followed them, collapsing the entrance and trapping them inside before pursuing them throughout the zoo.
The elephant was contained once survivors restored power and lured it into the Elephant Stage before closing the gate, trapping it inside.
Edit