Your deck is a bit too scattered to play with any consistency. I highly recommending running 4x most cards, and having very few 1x and 2x.

Let's get those 2 ofs out of the way first:

I would run x3 Banishing Light and x2 Hero's Downfall (5 total removal);

as well as 2x Feast on the Fallen and 2x Armament of Nyx (4 total buffs).

Total Non-Creatures = 9

Creatures:

Remove :

x1 Doomwake Giant x2 Herald of Torment

Add:

4x Master of the Feast

2x Athreos, God of Passage

4x Brain Maggot or 4x Spiteful Returned (Not both)

2x Fate Unraveler (-1)

4x Grim Guardian

4x Nyx-Fleece Ram (+1)

4x Underworld Coinsmith

4x Eidolon of Countless Battles

Total Creatures = 28

Total Non-Land = 37, Land = 23

35 Enchantments is nothing to scoff at. With 8 Constellation cards you're bound to be triggering with every drop. Eidolon of Countless Battles has 30 cards that trigger its +1/+1. Life gain with Underworld Coinsmith & Nyx-Fleece Ram will keep you afloat just fine.

Master of the Feast is an incredibly powerful 3 drop, worth the negative aspect. Couple him with Eidolon of Countless Battles or Armament of Nyx or Spiteful Returned , and you've got lethal in 2 or 3 turns.

Planeswalkers really do nothing for this deck, and seeing as you seem strapped for cash (comment #2) it brings down the cost of your deck.

I hope these are helpful, from one MTGer to another!

Segasaurus I think that your list is more aggro-oriented, with the use of Master of the Feast and Eidolon of Countless Battles . However, the deck I would like to build is more of a control deck, with plenty of removals and disruptions.

I am still thinking about the use of Doomwake Giant and Herald of Torment . I need more playtest to judge whether they are useful for my deck.

I would recommend Utter End over Silence the Believers - you're rarely going to cast it with an extra strive with 23 lands, I doubt you'll see other enchantment heavy decks (see below), and Utter End can hit 'walkers.

I'd also look at getting Temple of Silence to replace the Scoured Barrens - still comes into play tapped, but I'd argue the scry effect is > +1 life as you're not running things like Sunbond or Ajani's Pridemate that want you to gain.

Big problem I see: Back to Nature is basically a hard counter to your entire deck. There's a lot more enchantment hate out there: Erase , Deicide , Revoke Existence . I've seen Back to Nature in a lot of lists, and I've even seen it AND Erase - what's your game plan vs. an opponent who runs some removal main and boards in enchantment hate?