Images:

gw2-hero's-focusgw2-hero's-focus-2gw2-hero's-focus-3

Set:

Slot Item Name Trading Post Preview Code
Focus http://db.dulfy.net/item/64289 [&AgEh+wAA]

Where to Obtain:

Purchased from the Battle Historian for 100 WvW Tournament Claim Tickets. They are also automatically unlocked when you purchase the equivalent Mistforged Hero’s weapon skins