The creatures:
The low cost creatures (2 mana or lower):
Nightscape Familiar, used to lower the cost of your blue and red spells, useful for getting out Sewn-Eye Drake or Wildfire Eternal.
Vedalken Ghoul, chip the enemy slowly, likely won't be blocked to avoid taking the extra damage.
Grixis Grimblade, even more chip, the +1/+1 and deathtouch useful for defending you from enemy attackers.
High cost creatures (3 mana or higher):
Shambling Remains, used to chip the enemy, high power for a decently low cost.
Sewn-Eye Drake, unblockable chipping unless the enemy has reach or their own flyers, haste allows it to start dealing damage as soon as you can summon it, with one or more Nightscape Familiar these can be summoned and chipping right away.
Wildfire Eternal, this card is your ticket to victory, many combos with the high cost spells in the deck due to it's ability, casting Artful Dodge (which has flashback) before attacking guarantees a free spell cast of any of your spells, one of the many combos is to use it's ability to cast Behold the Beyond, pick out your Army of the Damned and then Burn at the Stake, allowing you to deal 39 damage next turn assuming you've only got the tokens from Army of the Damned out. Additionally you can use Cackling Counterpart to copy your Wildfire Eternal, meaning you've now got two that can be casting assuming you haven't drawn into another already.
The spells:
Instants:
Boulderfall, cast this with your Wildfire Eternal ability, wipe the enemy board(s) of creatures and deal a nice chip to them as well.
Cackling Counterpart, mostly useful for copying Wildfire Eternal, may also be used to copy any other creature you control.
Split Decision, less of a guarantee with this card, can be used to counter or copy an enemies spell depending on the vote, guaranteed copy of one of your own spells.
Stubborn Denial, bit of a gamble with this card, worth it for the low cost and if you've got Shambling Remains on the field it's a guaranteed counter.
Sorcery:
Army of the Damned, high cost, will likely not be playable without Wildfire Eternal, instant board swarm, pairs extremely well with the next sorcery.
Burn at the Stake, if you've cast this card the turn after Army of the Damned, you can dish out 39 damage in one turn making use of Wildfire Eternal's ability and Artful Dodge if necessary.
Artful Dodge, guarantee a free spell cast by using this on Wildfire Eternal, low cost huge return.
Behold the Beyond, tutor your win condition cards with this, unfortunately like with most of the high cost spells, this will likely be unplayable without Wildfire Eternal's ability.
Ghoulcaller's Chant used to return your important monsters from the graveyard.
Never / Return, useful for removing problem creatures/planeswalkers from the enemy board, and add a little bit of swarm to your board.
The lands:
Vivid Creek, Vivid Crag and Vivid Marsh all serve the same purpose, the time counters allow any colour mana in a pinch.
Sideboard:
Approach of the Second Sun, cast this using Wildfire Eternal, then cast Apex of Power next turn, you win.
Apex of Power, see above.
Cruel Ultimatum, use this card to toy with your opponent for fun!
Eternal of Harsh Truths, in case you're needing extra draw power, consider using these instead of Vedalken Ghoul or Grixis Grimblade.
Redirect, A low cost counter.
