Ballista elephant

Okay, have you ever seen an elephant before? They're really big and strong, right? Well, a long time ago, people used to train elephants to help them in battles. One way they did this was by putting big, heavy things on their backs, like a castle wall or a big metal spike. That way, when the elephant ran towards the enemy, it would be like a big, unstoppable force, kind of like a battering ram.

But people also wanted to be able to shoot things from the elephant, sort of like a giant bow and arrow. So they made something called a ballista. It's like a really big, really strong bow that can shoot things really far. Imagine a giant slingshot, but with sticks and ropes instead of rubber bands.

Now, imagine we put the ballista on the elephant's back. When the elephant runs towards the enemy, it can also shoot big arrows or rocks at them from the ballista on its back! It's like having a moving, unstoppable tank that can also shoot things really far. That's what a ballista elephant is!