Deck is designed to shut down or slow down opponents with naming cards and ghostly prison until you can win with planeswalkers.
The deck is largely enchantment-based in an attempt to keep it from being weak to removal. The strategy is also trying to 2 for 1 (or really 4 for 1) by making all copies of an opponent's card useless.
Our first three cards are something like the core of the deck in this case: they are enchantments designed to stall or halt the opponent's strategy. Hopefully, these are what give us the time to win with planeswalkers.
Runed halo: Great against go tall strategies like boggles and death's shadow. Can also be a near instant win against targeted or damage-based combo decks such as storm or ad nauseum.
Nevermore: Mostly good against combo or other control decks. We would primarily use this to stop combos that don't target us (think empty the warrens) or other planeswalkers. This is also good to stop some draw engines like chord of calling or collected company.
Ghostly Prison: I feel like this one is a bit obvious, but here goes. Prison is all about preventing our opponent from attacking. Well, at the very least, it's about taxing aggro strategies and slowing them down.
The next couple of cards consist of our spot removal. These should be pretty straight forward.
Oblivion Ring: Wide-reaching spot removal. Can be used for pesky artifacts or enchantments like worship, ensnaring bridge, or pithing needle. O-ring will often be a catch-all for win conditions or locks that our opponents top deck.
Fatal Push: Our only non-exile creature removal in the main. While spot removal is always timing dependent, these are best used on creatures we want to completely get rid of with extirpate.
Path to Exile: Faster, but not as wide-reaching as o-ring. Good for running out as a second spell on a turn and still getting resilient threats.
Next we are on to denial and game knowledge. These cards give us important knowledge on what to name and when.
Thoughtseize: One of the MVPs of the deck. Lets us see our opponent's hand, get a feel for what we are running against and steal their best card. These work really well with our copies of extirpate against combo. It's also important to get troublesome cards out of the way like aether vial.
Seek: While not as good at controlling our opponent as thoughtseize, seek gives us near perfect knowledge of our opponent's goings on. This will tell us the best threats to name. It also lets us gain a bit of life vs aggro or steal singles of win cons against some combo decks.
Control generally lives or dies based on its ability to draw cards. While we can't cantrip like blue, but we have some fairly powerful draw engines.
Phyrexian Arena: Basically an extra draw every turn. These are also often going to be removal bait.
Night's Whisper: Decently powerful, lets us grab two for two life.
Karn, Scion of Urza: Primarily a draw engine in our deck, but he can become a win condition if we get a lock and need some construct beats.
Extirpate: Something of an unusual card, extirpate helps in a lot of our strategies to get rid of troublesome cards. Against tron it can break tron after we kill one land. Against storm it can eat their grapeshot or empty the warrens while past in flame is on the stack. It can eat all copies of trouble creatures in aggro decks like death's shadow. It can also eat our opponent's bolts in burn after the first is cast. Really, extirpate is one of our MVPs by denying whole strategies to our opponents.
Finally, we come down to our win conditions: Gideon.
Gideon of the Trials: The more controlling of the two Gideons, trials is all about denying our opponents win just that extra little bit. When we have the lock, just start swinging with a resilient clock.
Gideon, Ally of Zendikar: Ally is probably our most straight up win condition oriented card. If need be he can keep up a trials emblem so that we don't die to a lucky top deck. Mostly though, he's going to make tokens or swing himself.
Sideboard quick run down:
Wrath and Damnation for aggro.
Damping Sphere for storm, tron, and ramp.
Leyline of Sanctity for burn, hand denial, storm, and other targeted combos.
Rain of Tears mainly for tron, but also for land based ramp.
Surgical Extraction for more graveyard hate and matchups where more extirpates help a lot.
Inquisition of Kozilek for when 4 thoughtseize isn't enough.
