Angelus: I've enslaved a handful of new walkers, and a creature that stores mana, Omnath. Thus it simply goes like this.
I use my Birds and Llanowar Slaves to create more mana, and ensuring I have the best land available, I usually enchant it to provide more mana. A good start.
Then the nexus of it all, a seemingly unnoticeable spell, but the downfall of them all. Prismatic Omen. My wonderful lands, become all types, producing just absolutely any color I so desire. Enlightened Tutor also helps me focus on this when I so desire it.
I've also ensnared some Elvish Visionaries, to produce a few weak sacrifices alongside their ability to help me recall more spells to my mind.
Omnath is a wonderful behemoth to guard myself, and also strike my foes down. And he's just so wonderful at storing all that excess mana I don't end up using.
The two blades I use are for special purposes. Body and Mind is for those pesky little defenses that make their controller indestructible. Thus wiping out their minds is the best follow-up. Feast and Famine provides my lands another glorious charge.
Sen Triplets, Lighthouse Chronologists, and Worship are all wonderful creatures and spells. Sen Triplets allows me to view into my foe's hand and lets me use his own spells, with his own mana, sometimes against himself! The Chronologists provide me extra time when I find it needed, and Worship is what all should do for me, allowing me to never die as long as I have one loyal attendant.
[B]W-B [/B]Venser is a wonderfully offensive card, allowing me to get an extra charge for my Omnath, reuse my Visionaries to their true extent, recharging another Walker, and untapping one of my creatures who've recently attacked. Add on his unblockable spell, and the Emblem of Exile, and he is a useful addition.
[Black]Liliana is such a pretty tool, destroying the most well-thought plans at times, and providing me the essential spell to victory, be it another Walker, to an Omnath, to Worship itself. Her ultimate spell while useful to me, is almost never used except in emergencies.
[Green]Garruk suits my mana color magnificently, and his ability to untap lands is just marvelous. Adding in his little scapegoats is a nice touch, but his ultimate is a perfect addition when I need that final boost.
[White]Elspeth speaks for herself. She provides that little touch of protection for herself with her Soldiers, adds a useful boost when I desire, and when I find my field desirable, her Emblem's protection is much appreciated.
Gideon Jura, provides an excellent warrior to any battle field given his natural ability to take battles on, headfirst. Consider his ability to make foes target him, as a blessing when protecting other Walkers. And if there's an annoying creature on the field, it makes them think twice of attacking, knowing Gideon will destroy it moments later.
Ajani Goldmane is a great healer, providing time for me to stall the battle further, and the very fact he can power up my allies to ridiculous standards in no time flat is astonishing. And if powered-up enough, they become perfect guards for him to charge up and power your creatures once more, creating a vicious cycle. Throw in the Avatar he is capable of forging, and I've won.
[Red]Koth is a situational little tool. A random card, but nice when needed. Prismatic Omen is the one thing making him useful, and the moment that's gone he's useless entirely. His untapping ability makes monsters out of my land and the mana they can provide is useful. Although the Red Mana Burst isn't really useful due to how Red isn't my color. Throw in his Emblem of making my Mountain-Forests incinerate players when I tap them, and he's a nice steady addition, although not heavily reliable. Oh, if only he was Green. Then we'd be best friends.
Chandra is a wonderful little fire for any deck, providing the ability of directly hurting a foe, eliminating any pesky threat, and upon reaching his greatest strength, eliminate most fields.
[Blue]
Ah, the most hated Mind Sculptor, Jace Beleren. He isn't the greatest asset here, and comes when he pleases at times. From drawing three cards I might find use for, ensuring my foe's next spell isn't instrumental in my downfall, removing those creatures that get powered up or cheaply thrown in, to utterly rendering one's mind asunder, Jace's one of the greatest asset to any deck, as time continues to show.
[Colorless]
Karn is an excellent remover, rivaling Jace, Liliana, and Venser in usefulness at times. His ability of exiling cards from a player's hand can be a great ability to use when the timing is right, but his ability to exile any permanent is just godly. Farewell opponent Planeswalker, Emrakul, or 20/20 Creature. His ability to restart a game is sometimes nice, when I need to teach my enemy a lesson.
[Blue-Black-Red]
Nicol Bolas, the epitome of destruction for anyone. Very difficult to use, even for me. But when utilized properly, deadlier then one can imagine. Start destroying their lands, enchantments, planeswalkers, artifacts. Start taking their creatures as your own to use against them in the most evil of ways. Then make them remove their hand, suffer damage, and lose a chunk if not all of their field.
The power I propose to you, used to be but a fleeting dream.