Unova Dex Completion (Seen)

If you have seen all the Pokemon from Unova Dex, you will be able to catch a shiny Haxorus.. You can actually "see" all Pokes from Unova Dex with a bit of effort without any friend or 2 Ds.. Victini is not included, so it's possible, even for a poor lonely people :).. However you will definitely need the use of GTS.. You will also need to be in Post Game to do this.. It might be too late to say this but, don't be a coward.. Battle all trainers you see, they will help you a lot in this..

Pokemon that you might missed:

• Ditto

- You can get a Ditto in Giant Chasm. Catch 2, one for personal use, one for in-game trade for Rotom.. Of course, Ditto is more important than just getting "seen"..

•  Buneary/Skitty

- You will have to go the hidden cave in Castelia City, Castelia Sewers (where you tagged with your rival).. From here, go down the stairs twice.. Then head west, you will eventually see a long stair that leads you outdoor.. You will be able to catch Buneary (Black 2) or Skitty (White 2) here..

• Shuckle

- You can get Shuckle in Seaside Cave, the cave at the south of 8th gym.. Go to the bottom/lowest floor, the place where you used to solve boulder puzzle.. Good luck finding one.

• Corsola

- You can meet a Corsola by "stepping" on ripping water in Seigaiha City..

• Yanmega

- Go to Route 3 and start hunting Yanma there.. If you see shaking grass, then go for it as well. You might be able to catch Yanmega..

• Zorua

- What you need is actuaaly Zoroark, but of course you will need Zorua to get it.. You can get Zorua from Rood in Driftveil City, in case you forgot to pick it up.. Then all you need to do is lvl it till evolves..

Pokemon that needs to be Breed:

• Briflim & Banette

- You can easily meet them outside the haunted mansion area .. Just breed them to get Brifloon and Shuppet respectively.

Pokemon that needs to be Caught and Evolve

• Seel

- You can find Seel via surfing inside Seaside Cave.. It will evolve to Dewgong at lvl 34..

• Bronzor

- You can find Bronzor in Abundant Shrine.. It will evolve to Bronzong at lvl 33..

• Female Combee

You can find Combee on Route 12.. It will definitely takes some time/luck to get a female one since it's just 78% being male.. It will evolve to Vespiquen at lvl 21..

Pokemon that needs Evolution Item

• Monkey Trios

- There's 3 ways to see them in battle. A battle with one of the Gamefreaks, tag battle with the ex-gym leaders (Cilan and his gang) or a trainer on Route 23 but you need Waterfall to reach her..

• Gliscor

- First, you will need a Razor Fang.. You can get it in Route 11, where you need Waterfall to get to the lower ground. Once you got it, attach to Gligar and lvl up it at night..

• Ninetales

- You can get a Vulpix in Abundant Shrine.. Then just use Fire Stone on it.

• Roserade

- Use Shiny Stone on Roselia.

Pokemon that needs to get from GTS:
(Don't bother going through Wanted, cause most of the Pokes they asked are Legends or Poke that you can't offer.. So instead put a Poke as an offer for the Poke you wanted.. And that doesn't mean you can put Patrat/Pidove for a Braviary etc.. Offer a reasonable ones!)

• The 1st stage starter Poke your counterpart used in Battle Subway

- It's the only starter out of the 3 that you have only seen its 1st stage.. Evolve the GTS-ed Poke.. Since you got it from trade, it will gain 1.5x/2x exp faster than a breed one.. Then breed it for another dex entry.. Since it's a starter, you can probably offer it for another good Poke in GTS..

• Braviary/Mandibuzz

- Depends on which version you are playing. If you are playing Black 2, you CAN get DW Mandibuzz. If you are playing White 2, you can get DW Braviary. Whichever it is, you will still need to get the other one from GTS.. Breed Braviary with a Ditto to get Rufflet.. As for Mandibuzz, you might want to breed with it with a male Poke (You can easily get Pidove to do the job). And of course you will get DW/ Vullaby for your dex entry.

• Delcatty/Lopunny

- If you are playing Black 2, you won't be able to see Skitty.. If you are playing White 2, you won't be able to see Buneary.. So now you will have to get the evolution of the Poke you didn't see through GTS.. Then of course, just breed it..

• Walrein

- You can only get Spheal/Sealeo in Winter.. So you MIGHT want to get a Spheal from GTS.. Then evolve it to Walrein..

Legendaries

• Kami Trio (Landorus, Tornados & Thundurus)

- Go to Route 7.. Enter the house on the right/closer to the cliff.. Talk to the old man, he will fill these 3 Pokes into your dex..

• Zekrom & Reshiram

- You get these entries from one of Team Plasma's grunts when you infiltrated their ship.. Go to the place where the Team Plasma's rest rooms.. The grunt will be in the second room on the left side.. If you missed it, TRY go to P2 Lab where their ship landed after you have beaten Elite 4 and talk to him..

Here's probably the Pokes you might have missed for Unova Dex.. I might missed some rare ones that you might not encounter commonly, so feel free to leave a comment to tell me which one you missed..

Nature Sanctuary
Once you have seen all the Pokes.. Go to Prof.Jupiter in Nuvema Town.. Talk to her and she will give you a License Card.. Now fly to Mistralton City, go to the airport building and talk to the women behind the counter.. You will then be "fly" to Nature Sanctuary.. Here, you will be able to capture Nuzleaf, Kecleon, Girafarig and Noctowl.. If you use fishing rod, you will be able to get HIGH LVL Magikarps.. Of course, the main dish is none other than the stationary shiny Haxorus..

Unova Dex Completion (Caught)
Since you have seen all the Pokes already.. You can easily get them on GTS now.. Of course it will takes some time.. :)