Imperial Centurion

[Falcus]

Every now and then when Alfgar is in Ul'dah, an NPC will appear north of Horizon on a Chocobo and you'll see loads of Imperials running around when they're there.
Talk to the NPC on the chocobo to join (similar to behest) and then go nuts and kill as many imperials as you want.
If you drive them away you get a chest which contains some deaspected crsytals (can range from 3 to 9 from my experience)

If you don't kill enough of them in a certain amount of time, they'll withdraw but you don't get the chest.

They're unrelated to the grand company quests.

And it's something like "My death means nothing in the empire's plans" or something like that.
I'm fairly certain on the "My death means nothing" part though.

[Zahak]

After hours upon hours of hearing the same death cry track over and over again I have come to the conclusion that he says..."My death means nothing...the empire is lalafells!" Bow down to us tall races of Eorzea! D:<

[Etienn]

I knew it was not GC, does not mean I should not be interested in GC's. I should try doing this event either way.

[Roaran]

"Camp Horizon is merely a setback!"