Muktol

Perhaps this halfdeck can help you:
http://www.mtgvault.com/muktol/decks/gw-halfdeck-infinite-mana/

If you want to win via "Helix Pinnacle" and defenders, then I would recommend using some green defenders like "Axebane Guardian" or "Overgrown Battlement" (If you want to go infinite I would add "Staff of Domination").
This would also enable you to remove "Khalni Heart Expedition" and "Cultivate" and add some protection-spells like "Swiftfoot Boots", "Ranger's Guile", "Vines of Vastwood" and so on.

Greetings
Muktol

I would change from "Gatekeeper of Malakir" to e.g. "Stromkirk Captain", "Vampire Nighthawk" and so on. It can be pretty hard to pay triple {B} in a B/R deck.

Greetings
Muktol

I mean no offense, but please take a look at http://www.mtgvault.com/muktol/decks/how-to-build-a-deck/
Try to reduce the number of cards uses in your deck to 60 or 62, but no more. Every card more in your deck lowers the chance of drawing cards you want to have in your hand for your strategy.

Greetings
Muktol

If it would be my deck I would do some changes here:
-2 "Ember Hauler"
-4 "Mogg Flunkies"
-1 "Riot Piker"
+1 "Foundry Street Denizen"
+1 "Goblin Chieftain"
+2 "Goblin Wardriver"
+3 "Bloodmark Mentor" or, if you have the budget, "Legion Loyalist"

Greetings
Muktol

Some suggestions, based on my R/W pauper human deck (http://www.mtgvault.com/muktol/decks/rw-pauper-humans/)
Cavalry Pegasus ({1}{W}; 1/1; Flying; Whenever Cavalry Pegasus attacks, each attacking Human gains flying until end of turn), Doomed Traveler ({W}; 1/1; When Doomed Traveler dies, put a 1/1 white Spirit creature token with flying onto the battlefield), Kruin Striker ({1}{R}; 2/1; Whenever another creature enters the battlefield under your control, Kruin Striker gets +1/+0 and gains trample until end of turn), Riot Ringleader ({2}{R}; 2/2; Whenever Riot Ringleader attacks, Human creatures you control get +1/+0 until end of turn)

Gather the Townsfolk ({1}{W}; Put two 1/1 white Human creature tokens onto the battlefield. Fateful hour -- If you have 5 or less life, put five of those tokens onto the battlefield instead), Thatcher Revolt ({2}{R}; Put three 1/1 red Human creature tokens with haste onto the battlefield. Sacrifice those tokens at the beginning of the next end step)

I also would add some (cheap) duallands in addition to "Transguild Promenade", e.g. "Boros Garrison", Boros Guildgate

Greetings
Muktol

I built a deck with a similar idea, but I wanted it to be rather mid to lategame than aggro.
I'm using "Chronozoa" and "Power Conduit" to generate and move counters. "Contagion Engine" to proliferate and "Wing Splicer" as finisher.

Greetings
Muktol

Some suggestions based on my B/R vampire deck (http://www.mtgvault.com/muktol/decks/br-tribal-vampire/)
Remove "Child of Night" and add "Bloodghast" instead. This built seems to be more aggro than midgame, thus lifelink may not be needed here. But a creature that comes back (and profits from "Stromkirk Captain") can be very good.
Decide either to use "Curse of Stalked Prey" or "Rakish Heir", both may be a little bit too much. The curse is harder to remove for your opponent, the Heir can be used as additional blocker.
So you end with 3 free slots. I would use them to increase "Curse of Stalked Prey" or "Rakish Heir" to 4 and add 2 "Vampire Nocturnus". You only have 28 (4 creatures, 4 spells, 20 lands) non-black cards in your deck, so his ability should activate quite often. If you want some more card manipulation, try "Read the Bones" instead of "Sign in Blood"

Greetings
Muktol

I would reduce "Instigator Gang" by 2 and add "Reckless Waif" instead, to speed you play up a little bit.
Furthermore I would remove "Caravan Vigil", add some duallands and either something to draw cards (e.g. Infiltration Lens) or some removal/ protection (e.g. "Searing Blaze" or "Ranger's Guile)

Greetings
Muktol

Legal, but expensive to play.
If you're up against (modern legal) combo decks, they can finish you with turn 3-4. Other aggressive decks also won't take any longer and control based decks mostly feature something against spells/ enchantments.

"Sylvok Lifestaff" can be used when going after an opponents deck which uses many burn/ destrcution spells. As 90% of the decks you will encounter feature roughly 1/3rd spells of whom a great deal will be removal it is a good thing to think about something to take advance of it. The lifestaff at least gives you life back, better would be to draw a card, or to prevent the creature from being targeted (e.g. "Swiftfoot Boots´")
"Darksteel Citadel" only works good in decks with metalcraft or to increase the number of artifacts you are playing, e.g. for "Cranial Plating". But if you feel that it throws your mana-curve out of balance then it's not worth adding.
"Bladed Pinions" could also be worth taking a look at if you find it difficult to get your attackers through.
"Bonesplinter" and "Shuko" are nearly the same from the mana/ boost costs. Shuko brings +1/+0 for {1}; Bonesplinter +2/+0 for {2}

I would remove "Kor Outfitter" as you don't have any equipment that costs more than cc2 to equip. Which are exactly the mana-costs of the Outfitter. I would rather play some more equipments (See suggestions)
There are some good alternatives to "Kor Skyfisher" if you want something flying, which also fit into this deck. either on the human side (search for "Auriok") or some good Kor's

Suggestions, based on my monoW pauper equipment deck (http://www.mtgvault.com/muktol/decks/monow-pauper-equipment-2/) and my monoW Kor equipment deck (http://www.mtgvault.com/muktol/decks/monow-kor-equipment/)
Bonesplitter ({1}; {1} to equip; Equipped creature gets +2/+0), Horned Helm ({2}; {1} to equip; Equipped Creature gets +1/+1 and has Trample), Leonin Scimitar ({2}; {1} to equip; Equipped creature gets +1/+1), Sylvok Lifestaff ({1}; {1} to equip; Equipped creature gets +1/+0. Whenever equipped creature is put into a graveyard, you gain 3 life), Infiltration Lens ({1}; {1} to equip; Whenever equiped creature becomes blocked you may draw 2 cards), Basilisk Collar ({1}; 2 to equip; quipped creature has deathtouch and lifelink), Cranial Plating ({2}; {1} to equip; Equipped creature gets +1/+0 for each artifact you control), Swiftfoot Boots ({2}; {1} to equip; Equipped creature has hexproof and haste)
Kitesail Apprentice ({W}; 1/1; As long as Kitesail Apprentice is equipped, it gets +1/+1 and has flying), Etched Champion ({3}; 2/2; Metalcraft: Etched Champion has protection from all colors as long as you control three or more artifacts), Ornithopter ({0}; 0/2; Flying), Puresteel Paladin ({W}{W}; 2/2; Whenever an Equipment enters the battlefield under your control, you may draw a card; Metalcraft - Equipment you control have equip 0 as long as you control three or more artifacts)
Darksteel Citadel (Modern legal artifact land)
Dispatch ({W}; Tap target creature; Metalcraft - If you control three or more artifacts, exile that creature), Steelshaper's Gift ({W}; Search your library for an equipment card, reveal that card, and put it into your hand.Then shuffle your library)

Greetings
Muktol

Some suggestions, based on my U/G evolve aggro deck (http://www.mtgvault.com/muktol/decks/gu-simic-aggro/); built for Standard-Block: M13, Innistrad, M14 and Return to Ravnica

Dryad Militant ({G/W); 2/1; If an instant or sorcery would be put into a graveyard from anywhere, exile it instead)
Rancor ({G}, Enchant creature; Enchanted creature gets +2/+0 and gains trample. When Rancor is put into a graveyard from the battlefield, return Rancor to its owner's hand)
Bioshift ({G/U}; Move any number of +1/+1 counters from target creature onto another target creature with the same controller), Hunger of the Howlpack ({G}; Put a +1/+1 counter on target creature. Morbid -- Put three +1/+1 counters on that creature instead if a creature died this turn), Simic Charm ({G}{U}; Choose one — Target creature gets +3/+3 until end of turn; or permanents you control gain hexproof until end of turn; or return target creature to its owner's hand)
Hinterland Harbor (Dualland)

Greetings
Muktol

I used "Sigil of Sleep", "Hidden Strings" and "Shadow Slice" in my U/B Pauper unblockable deck. "Phyresis" and some cheap equipment's could also be an interesting option.
Maybe "Tormented Soul" if you want some more unblockable creatures

Greetings
Muktol

I would trade 2 "Reap What Is Sown" for 2 "Blessings of Nature".
"Timely Reinforcements" and "Thraben Doomsayer" could also be worth taking a look at.

Greetings
Muktol

I would try to remove the creatures with 'sacrifice' effects: "Grotag Siege-Runner" or "Ember Hauler". It will be hard enough for real new players to get along with the rest of the cards as every one of those has an effect.
Giving him the choice to sacrifice a creature may be more frustrating than helping as it is rather hard to judge when to do this in the beginning and not forget that you are able to do so. I would concentrate on 2-3 more or less easy effects for such decks.
Apart from that this is a a very good idea and a good deck.

Greetings
Muktol

*like* for the great description
You could add some searchlands (e.g. Evolving Wilds) to reduce the number of lands you will draw later on, and to activate the landfall ability from bloodghast more often.
I would try ro play "Kalastria Highborn" mainboard, as most decks today use 1/3 of their deck for spells and most of those will be removalspells. But that depends also a little bit on your game-surrounding. Try a 2/2 split between the Hexmage and Kalastria for some tests.

"Tragic Slip" could be an interessting card, as there are always creatures dying in games, and this lets you remove a X/13 and even indestructible will be no problem.
"Shadow Alley Denizen" can give one (or more, depends on how many black creature spells you play in a turn) of your strong creatures unblockable, which can be interesting in some games.

Greetings
Muktol

As hard as it may sound but, if you want to link this to new players I would clean up the comments and only let those remain, which help to improve or clarify your text. Otherwise they may just be overwhelmed by the sheer number of comments.

Looks like a revision from the "Vampire Onslaught" event deck.
Here is mine, perhaps you can take some ideas from there: http://www.mtgvault.com/muktol/decks/vampire-onslaught-revised/

I would lower the number of finishers a little bit, to get some more creatures to do the wetwork and to lower your manacurve a little bit.

Greetings
Muktol

*like*
A more general approach I did once: http://www.mtgvault.com/muktol/decks/how-to-build-a-deck/
Never was as popular as this one but maybe you can take some ideas from there ;)

Greetings
Muktol