The road is a metephor for lunch. Crossing it is the act of eating it and then you burp. Thus your journey is completed. Plus there are kittens, baby ducks and bunnies.

*HUGGLES*

But one should never cross the road. It would get mad, open up and swallow you whole.

The real question is, what is an Ixzion?

Yeah that is true. If we know what is an Ixzion then we will understand what this "ixzion" wants to do.

I think it's a lightning-elemental unicorn.

@NLY - isn't that LONE's metaphoric road?

An Ixzion must some sort of Road crossing device.

If that were to be true then the possible answer is that said device was utilized by another party to cross the road, thus the answer to why did Ixzion cross the road goes something like:

Because _______ utilized him to do so.

and the rest of the mystery is to find who or what goes in the blank.

Hey! All my _________ are gone. And not just __________ but the word _________ too! An Ixzion must be a _________ thief!

An Ixzion in accord with Enix Squaresoft's Final Fantasy, is a Powerful Godlike Horse/Unicorn with Thunder and Lightning Abilities.

Without an Ixzion, we wouldn't be able to generate the 1.21 Jigawatts required to activate the flux capacitor.

No, that's called Ixion. I have a 'Z' in my name. And I made it years before FFX came out.

Darn it, I should've asked about that in my test!

So then tell us, What exactly is an Ix"Z"ion?

Because he was hungry.