Oliphaunt

Grey as a mouse,
Big as a house,
Nose like a snake,
I make the earth shake,
As I tramp through the grass;
...
If ever you'd met me
You wouldn't forget me.
If you never do,
You won't think I'm true;
But old Oliphaunt am I,
And I never lie.

John Ronald Reuel Tolkien - The Lord of the Rings