The mouse hated the frog, and the frog hated the mouse.
Over time, their hatred turned into outright warfare.
"I shall rule the swamp," declared the mouse.
"Never!" replied the frog. "This swamp is mine!"
The mouse attacked, ambushing the frog, but the frog fought back bravely. They both wore armor made of dried mud and wielded tiny swords made from the marsh-grass
As the battle dragged on, a hawk saw what was happening and swooped down, catching both frog and mouse unawares, gobbling first one and then the other.
Thus ended the war between the frog and the mouse.
Inspired by: Mille Fabulae et Una, a collection of Latin fables that I've edited, free to read online. I am not translating the Latin here; instead, I am just telling a 100-word version of the fable.
Notes: This is fable 198 in the book, which is Perry 384.