Vostok

Duel Decks don't change the format legalities of cards.

Opinions:
Drop all the other equipment except fireshrieker. Drop the enchantments.
+4 Gitaxian probes, +4 Signal Pest, +2 Glint Hawk, +1 Memnite, +2 Judge's Familiar

If you insist on other wincons drop the Vanguard add in Trepanation Blade, Pennon Blade, or Ogre's Cleaver.

He could replace lands with Gitaxian Probes.
It increases the strain on his life but it gives vital information while speeding him through the deck...

Deck now Modern, so no more ponder...
Suggestions ? Sideboard ?

I want to keep it modern legal, and would prefer not to spend too much on improvements.
All suggestions still welcomed...

Still brewing. Duals are for sideboard options...

Out : Pontiffs, and one each of Lord, doom and downfall.
In : 2 Erebos, 2 whips, 1 more Read the Bones

Erebos will usually be an indestructible creature; he and bones get you card draw; whip gives you lifegain and recursion to make everything happy.

While in "Deck Details" of your own deck if you hover your cursor over the card name several icons appear.
Clicking on the number allows you to edit it.
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Adding Erebos, his whip or both ?

To quote Gavin : "...devotion is already a snowbally mechanic—when you have high devotion, you tend to be ahead since that requires a lot of nonland permanents..."

I'm trying a version with Gruul sideboard so if you have any suggestions that would help.
http://www.mtgvault.com/vostok/decks/big-rg-hunter/

Add a way to draw more cards. Your had is going to empty in the first few turns then you'll be stuck topdecking.
Based on your creature theme I suggest : Infiltration Lens, Slate of Ancestry, Skullclamp, or Diviner's Wand.
Might also want the Elixir as I suggested in pocs' deck.

I suggest Ravenous Rats over Bog and I suggest Elixir of Immortality over Horn so you can recycle your cards.

It's uses are legion.

It's an equipment that comes with it's own creature.
Instant speed 1 damage kills many creatures.
The +1 toughness can be enough to break creature stalemates.
In this deck it activates the morbid trigger on Tragic Slip. It also combos with gravecrawler and messenger.

What do you want to do with your goblins ? How do you want to win ?
The answer to these questions will guide your deck building choices.

Androstosity's point about consistency is an important one. The more copies of a card, the more likely you'll draw it.

The one thing I'll tell you to add is 4x Goblin Matron.

Here's a version I made based on another deck:
http://www.mtgvault.com/ViewDeck.aspx?DeckID=355474

First, down to 20 land.
Add 4 Mogg Flunkies and 4 Goblin Grenade
Trade the Kindled Fury for Shock
Drop one each of Krenko and Elixir and add 2 Reforge the Soul

The problem with Assault is that you HAVE to attack each turn. Not worth the 1 extra token a turn.

No Leaf-Crowned Elder ?

I think Lord of Tresserhorn would work as the general...

Let's try this again.

What do you want the deck to do ? Make lots of goblins using Krenko.
To that end you want lots of goblins in play when you cast Krenko and for him and the goblins he will make to have haste.

We'll start at the cheapest to cast and work our way up.

Goblin Lackey is the dream. Possibly getting krenko out 2nd turn would be huge.
Other good choices : Goblin Arsonist(incentive not to block), Goblin Grappler(make them block), Goblin Sledder or Mogg Raider(sac blocked goblins to make unblocked ones bigger), Mogg Fanatic

At 2, Warren instigator is AWESOME ! Put in 4 if you can.
Also good : Bloodmark Mentor, Goblin Lookout, Goblin Wardriver, Mogg Maniac, Mogg War Marshal

Three of each lord is fine, but should have 4 matrons. She can get Krenko or whichever other goblin you want.

Horde of Boggarts works like Reckless but with the War Drums ability instead of haste...

Rest of the deck : Fodder/Krenko's Command, War Strike, and Grenade.
And because your curve is so low you can go down to 19 or so land.

Here's a version I made based on minor changes:
Deck link: http://www.mtgvault.com/ViewDeck.aspx?DeckID=355474

Rollng Stones allows defenders to attack.
Souls of the Faultless causes attackers to lose life and you gain it.
Wall of Souls deals damage equal to what it takes.
Warmonger's Chariot equips for +2/+2 and ability for a defender to attack.