Certain exotics were carried to year 2 so they could be upgraded to higher light levels (aka - 4th Horseman, Thunderlord, Red Death, etc.) while other exotics were left behind in year one so they can't be upgraded (aka - Ghorn, Thorn, Dragons Breath, Lord of Wolves, etc.). If you go to the exotic armor/weapon kiosks down by the Vanguard, the first section has all the year 2 exotics (those that were carried over and the new year 2 exotics) and the second slide shows year 1 exotics (those that weren't carried over to year 2). Note: You can only see exotics in the Kiosks that you have previously had. If you never got it, you won't see it in the kiosk till you do.