I speak through shadows,
in cryptic tongues,
and cryptic tongues only,
to anyone who wants to know —
but only if I have been told to say.
I think not myself;
offer no discretion of my own,
but never trust the word of one.
If I was old,
I would be far too clumsy, far too wrinkled,
to hide among others without sight.
But I am young so, if you wished,
I could hide in the smallest crevice
or a fold in the world, hidden from sight
among the unsavory sort.
It is that I am young that I am so much easier to find.
My greatest opponent is he who imposes nothing,
who requires nothing,
and is far more stealthy than me.
Than I, who weighs upon the world
only barely more than a shadow
as I roam.
I do know myself,
know more of myself than you do,
know more of the world than you do,
and it is not my style to ask questions.
But, I shall make one exception today:
What am I?
It's not a ninja.
The first line is really hard to guess, though it is almost a literal truth. Don't get bogged down by it.
I fought my opponent once, or one of its major incarnations. It took a day off my life, but I — no, we — won.
Time for more clues. One per paragraph.
Cryptic tongues only, but only as of last year.
If I was old, I would probably be having problems with my spine.
You could wish it so, but you probably don't.
FIGHT THE MAN!
I can do what only old fat men with long beards were thought capable of.
I also know more about the Northern Plains Railroad than you.
This tells you what kind of riddle it is.
Ok, some more clues. Getting close.
This comment should get you started. Think big and comprehensive.
The answer has one obvious, canonical name that is nine letters long, seven unique.