Muktol

@ Jessie: Search lands are used to decrease the chance of drawing a land. If you play and use a search land, you have effectively reduces the deck by 2 lands, wich gives you a better chance to draw damage spells.

@ seantarver23: I don't know much about legacy burn, but I would reduce "Fireblast" by 1 and add a third "Reverbrate" or "Searing Blaze". "Browbeat" could also be interesting for you.

Greetings
Muktol

First impression: You need to get some cheap (mana) creatures to sacrifice and get back from the grave as exchange for some of the expensive ones. A good second sac-outlet would also be useful as you shouldn't rely just on "Maw of the Obzedat"
Just a small hint: Regenerate won't work 'against' sacrifice.

Set creatures:
4 Reassembling Skeleton
3 Maw of the Obzedat (+1 as you always want to have one on the field, but don't need a second one, like a legendary)
4 Orzhov Pontiff (+3 buff or baordsweeper, depending on the situation)
2 Nested Ghoul
2 Teysa, Envoy of Ghosts
=15
Set spells:
4 Altar's Reap (+1 carddraw is never a bad thing)
2 Profit // Loss
=6
= 15 (Creatures) + 6 (Spells) + 20 (Lands) = 41 ... 19 free slots to use

So here are the suggestions I can think of:
From my pauper sacrificing deck (http://www.mtgvault.com/muktol/decks/bw-paupervampire-sacrificing/)
Azorius Arrester ({1}{W}; 2/1; When Azorius Arrester enters the battlefield, detain target creature an opponent controls...comes, detains, can block or gets sacrificed)
Driver of the Dead ({3}{B}; 3/2; When Driver of the Dead dies, return target creature card with converted mana cost 2 or less from your graveyard to the battlefield...comes, gets saced and brings a cc2 creature back to your hand)
Loyal Cathar ({W}{W}; 2/2; Vigilance; When Loyal Cathar dies, return it to the battlefield transformed under your control at the beginning of the next end step: Unhallowed Cathar; 2/1; Unhallowed Cathar can't block...can be saced twice or once and then buffed up as zombie)

From my monoB sacrifice (http://www.mtgvault.com/muktol/decks/monob-sacrifice-2/)
Sylvok Lifestaff ({1}; {1} to equip; equipped creature gets +1/+0. Whenever equipped creature is put into a graveyard, you gain 3 life...sideboard material when you feel that you need some extra life)
Blood Artist ({1}{B}; 0/2; Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life...converts dying creatures into damage and life)
Nether Traitor ({B}{B}; haste; shadow; Whenever another creature is put into your graveyard from play, you may pay {B}. If you do, return Nether Traitor from your graveyard to play...comes again from the grave for only {B})
Undercity Informer ({2}{B}; {1}, Sacrifice a creature: Target player reveals cards from the top of his or her library until he or she reveals a land card, then puts those cards into his or her graveyard...Sideboard material: Converts your deck from beatdown to mill)
Grave Pact ({1}{B}{B}{B}; enchantment; Whenever a creature you control is put into a graveyard from play, each other player sacrifices a creature...beside the triple {B} costs there is just one thing to say: Ouch!)
Tragic Slip ({B}; Target creature gets -1/-1 until end of turn. Morbid -- That creature gets -13/-13 until end of turn instead if a creature died this turn...most of the time you should be able to trigger the morbid effect)

From my B/W vampire sacrifice (http://www.mtgvault.com/muktol/decks/bw-tribal-vampire-sacrifice/)
Cauldron Haze ({1}{B/W}; instant; Choose any number of target creatures. Each of those creatures gains persist until end of turn...they go, the come again and are ready to go again)

So what I would use from these suggestions:
4 Blood Artist, 4 Nether Traitor, 3 Cauldron Haze, 4 Tragic Slip, 3 Grave Pact
If you want to rely more on zombies/ skeletons then "Death Baron" and "Cemetery Reaper" could be worth taking a look at.

Another way could be to use undying creatures (tough they are rather rare) and "Cauldron Haze" as +1/+1 and -1/-1 counters negate each other. With one "Cauldron Haze" you could sac a creatures 4 times until it is really on the graveyard.

Greetings
Muktol

Some friends told me that I tend to do drastic revisions, so if you aren't afraid of that, I will take a look at it :)

"Warren Instigator" works like a charm with "Infiltration Lens", and if you manage to get your creatures unblockable then it's GG for your opponent most of the times. But if you don't then you will need some carddraw, to get what you want.
Sentimental thing...accepted ;)

Some suggestions, based on my monoR goblin deck (http://www.mtgvault.com/muktol/decks/monor-tribal-goblins/)
I would take "Dragon's Claw" out and add 2 more "Quest for the Goblin Lord" instead. The lifegain should be pretty low and you loose some possible speed through the artifact.
Remove "Goblin Arsonist", the 1 additional damage can be used to remove some support creatures from your opponent, but if you keep some pressure on him, his supporters won't be of much.
Remove "Goblin Shortcutter" a single creature which can't block won't be of much use in a goblin deck, and this deck wan't to get as many creatures as possible unblockable.
Reduce "Horde of Boggarts" by 1-3 as it is rather a (second) finisher.
Remove "Riot Piker", personally I really dislike such 'has to attack' creatures.

Some ideas to replace the removed cards:
Infiltration Lens ({1}; {1} to equip; whenever the equipped creature gets blocked, draw 2 cards)
Blood Moon ({2}{R}; enchant; Nonbasic lands are Mountains.)
0-2 "Goblin Bushwhacker" ({R}; 1/1; kicker {R}; when Goblin Bushwhacker enters the battlefield, if it was kicked, creatures you control get +1/+0 and gain haste until end of turn), 0-4 "Goblin Wardriver" ({R}{R}; 2/2; battle cry), 0-1 "Krenko, Mob Boss", 0-4 "Mogg War Marshal" ({1}{R}; echo {1}{R}; When Mogg War Marshal comes into play or is put into a graveyard from play, put a 1/1 red Goblin creature token into play), 0-2 "Warren Instigator, 0-2 "Purphoros, God of the Forge" ({3}{R}; Whenever another creature enters the battlefield under your control, Purphoros deals 2 damage to each opponent; {2}{R}: Creatures you control get +1/+0 until end of turn)
0-2 "Nykthos, Shrine to Nyx" ({T}: Add {1} to your mana pool; {2}, {T}: Choose a color. Add to your mana pool an amount of mana of that color equal to your devotion to that color)

Greetings
Muktol

My monoW Human deck (http://www.mtgvault.com/muktol/decks/monow-tribal-human-wheeny/) started very simillar to this, but I changed it as I learned many things through some local matches
Some suggestions:
Change from "Accorder Paladin" to "Hero of Bladehold"; cc2 vs cc4 but the Hero brings some littl friends with him that benefit instant from his battlecry.
Change from "Elite Inquisitor" to "Kazandu Blademaster"; they cost the same and do the same, but the Blademaster profits from other Blademasters played later.
Remove "Gideon's Lawkeeper"; a rather defensive creature that most of the time will not be able to attack or defend as you will tap him to tap some of your opponents attackers/ defenders. Total useless against utlity creatures.
Sideboard "Grand Abolisher"; he can be used if you see that your opponent does many battletricks in your turn

Some cards you could take a look at:
"Mentor of the Meek" ({2}{W}; 2/2; Whenever another creature with power 2 or less enters the battlefield under your control, you may pay {1}. If you do, draw a card), combined with "Thraben Doomsayer" ({2}{W}, 2/2; {tap}: Put a 1/1 white Human creature token onto the battlefield. Fateful hour -- As long as you have 5 or less life, other creatures you control get +2/+2.) you get a card and a 1/1 human token for {2} every turn.
"Student of Warfare" ({W}; 1/1; Level up {W}: Level 2-6: 3/3, First strike; Level 7+:4/4, Double strike)
"Call to Serve" ({1}{W}; enchanted creature gets +1/+2 and gains flying) I love this one in combination with "Champion of the Parish" and/ or "Silverblade Paladin". Gives your opponent a tough flying doublestriker that only grows stronger in longer games)
"Elspeth Tirel" ({2}{W}{W}, planeswalker; +2: You gain 1 life for each creature you control. -2: Put three 1/1 white Soldier creature tokens onto the battlefield. -5: Destroy all other permanents except for lands and tokens.)

Greetings
Muktol

The problem I see with "Bloodchief Ascension" is that you want to have a rather defensive deck, which focuses on bringing out enough creatures/ tokens and defend them, to defeat your opponent with a strike from "Blasphemous Act" in combination with "Blood Artist". Basically a good Idea, but how do you want to get those 2 damage per turn to your opponent? Remember, the person on the other side of the table just won't sit there and say 'beat me, beat me please' ;)

So if you want to stick with this plan I first would change from "Lightning Bolt" to "Searing Blaze" ({R}{R}; instand; Searing Blaze deals 1 damage to target player and 1 damage to target creature that player controls. Landfall - If you had a land enter the battlefield under your control this turn, Searing Blaze deals 3 damage to that player and 3 damage to that creature instead). It gives you the possibility to remova a creature and nevertheless deal damage to an opponent. The double {R} (or {B} as other cards could have) in the manacosts could get a problem, but that's for later.
Second I would change from "Captivating Vampire" to "Stormkirk Captain". ({1}{R}{B}; 2/2; first strike; other vampires you control get +1/+1 and first strike). "Captivating Vampire" works great with many (7+) vampires arround, otherwise it will leave you wide open for a counter-attack. I really love first strike on defensive creatures as your opponent will always be scared of them and search for a way to remove them, leaving the rest of your plan intact. The other plan would be to add some hexproof equipment like "Lightning Greaves" or "Swiftfoot Boots", at last a good idea for your sideboard if you see that your opponent uses masses of point removal spells.

As for the pointremovals/ boardsweepers: I would change from "Feast of Blood" to something like "Terminate", or "Tragic Slip" and remove "Killing Wave" for 1 more "Blasphemous Act" and a free slot for the deck. There is a little danger in having only 1 finisher in your deck ("Extirpate"/ "Surgical Extraction" are played in many competitive decks) but that depens stong on your game surroundings.

I would perhaps change from "Underworld Connections" to "Read the Bones" as it digs faster and deeper (but not as continual as "Underworld Connections"). Another alternative could be "Sign in Blood" as it could also serve as "Shock" to defeat your opponent.

In my B/W pauper sacrificing deck (http://www.mtgvault.com/muktol/decks/bw-paupervampire-sacrificing/) I played with the idea of using "Undercity Informer" to change from beatdown to mill, perhaps also worth taking a look at, at least for the sideboard.

Greetings
Muktol

What is the strategy you want to use with this deck? There are 2 possible ways for you: Control or aggro. At the moment you have a mix of both, so you should decide how you want to achive your win over your opponent.
I mean no offense but you might want to read my deckbuilding guide (http://www.mtgvault.com/muktol/decks/how-to-build-a-deck/), I tried to write down some do's and don'ts for beginners, and some basic deckbuilding strategys.

Greetings
Muktol

I would add some more creatures (2-4 should be enough), take a look at "Ichorclaw Myr" and/ or "Signal Pest".
Furthermore I would change from "Giant Growth" or "Contagion Clasp" (which is rather expensive to play here, infect normally tries to be fast as hell) to "Rancor".

In my own monoG Infect deck (http://www.mtgvault.com/muktol/decks/monog-infect/) I play "Mutagenic Growth", "Vines of Vastwood" and "Bonesplitter" as further buff-options. "Rangers Guile" would be a possible spell to protect your creatures.

Greetings
Muktol

Personally I'm no big fan of "Foundry Street Denizen" in decks that don't use "Krenko, Mob Boss" or a huge load of summoning spells like "Krenko's Command". He will get +1 or +2 per turn, depending on what you draw, and what you are able to play. The problem is, that he has no evasion or trample, so that even a small x/1 can block him. If you don't play any spells he is a 1/1 without any usefull ability.
I would remove "Akki Avalanchers" for something like "Legion Loyalist", "Mogg War Marshal", "Warren Instigator" or "Quest for the Goblin Lord".

Greetings
Muktol

I would try to reduce the number of different spells and increase the number of the remeining ones, to give the deck some continuity.
I don't mean to offend you, but you could find some tipps in my deckbuilding guide: http://www.mtgvault.com/muktol/decks/how-to-build-a-deck/

Greetings
Muktol

Some suggestions based on my own monoR Goblin deck (http://www.mtgvault.com/muktol/decks/monor-tribal-goblins/)
Remove "Foundry Street Denizen" and add "Quest for the Goblin Lord" ({R}; enchantment; Whenever a Goblin enters the battlefield under your control, you may put a quest counter on Quest for the Goblin Lord. As long as Quest for the Goblin Lord has five or more quest counters on it, creatures you control get +2/+0) instead. It buffs all of your creatures and without spells like "Dragon Fodder", "Kuldotha Rebirth" or "Krenko, Mob Boss" himself, "Foundry Street Denizen" won't get that big. Also he lacks trample, so even a simple 1/1 could block him.
As you are using "Goblin King" you could give "Blood Moon" ({2}{R}; enchantment; Nonbasic lands are Mountains.) a try. This could extremely slow your opponents when they are using many non basic lands.

Greetings
Muktol

If you're using a whole load of swords you should try to reduce the mana-costs of the other artifacts.
I would also increase the number of "Swiftfoot Boots" to 4 and maybe add "Ring of Evos Isle" to give your creatures some protection.
You could also try to reduce the number of lands by 1-3 as your manacosts are rather low, and "Puresteel Paladin" lowers them further. But do some testgames to ensure you get enough mana.

Greetings
Muktol

Keep the Lavamancer, I talked with some friends, who specialice on burn, and they said that the Lavamancer is set in many burn deck.
Personally I simply don't like exiling cards from my grave, and the damage is 'just' a "Shock", but it uses a ressource that otherwise would be left unused ;)
Deppending on your game-surroundings you could use "Blood Moon" in your main deck,

I would be affraid of not drawing a creature with only 12 in the deck. But some testgames/ testdraws should show if that fear is eligible.
You could also try to lower the number or Forest by 1-2, as you have rather low manacosts (My own monoG Infect deck http://www.mtgvault.com/muktol/decks/monog-infect/ plays with 18 lands)

Don't know GyKx's deck but I would use some more creatures. "Blight Mamba" or "Signal Pest" could be used to fill up the ranks.
I'm a fan of "Evolution Charm" as it is really flexible.
Maybe change to some duallands or searchlands to make shure you get the mana you need.

Greetings
Muktol

I would reduce the number of cretaures a little bit (e.g. remove/ sideboard "Grim Lavamancer")
Furthermore I would remove "Char" as it is rather expensive to play and "Pulse of the Forge" because you want to be fast and thus lower your opponents lifepoints faster than he does yours.
An alternative could be "Browbeat" and/ or to increase the number of "Magma Jet" in the deck.

Greetings
Muktol

With all those fog-elements I would use "Isochron Scepter" ({2}; Imprint: When Isochron Scepter comes into play, you may remove an instant card with converted mana cost 2 or less in your hand from the game. {2}, {tap}: You may copy the imprinted instant card and play the copy without paying its mana cost.)

Other cards with might help you would be:
Kami of False Hope ({W}; 1/1; Sacrifice Kami of False Hope: Prevent all combat damage that would be dealt this turn), Primeval Titan ({4}{G}{G}; 6/6; trample; whenever Primeval Titan enters the battlefield or attacks, you may search your library for 2 lands and put them into play tapped)
Ethereal Haze ({W}; Prevent all damage that would be dealt by creatures this turn)
"Hallow" ({W}; Prevent all damage target spell would deal this turn. You gain life equal to the damage prevented this way) could be used in your sideboard.

Greetings
Muktol

Decide if you want to use either "Malakir Bloodwitch", "Mirri the Cursed" or "Drana, Kalastria Bloodchief"" as finisher. If you stay with "Drana, Kalastria Bloodchief"I would reduce the number of by 1-2 (legendary)
Remove "Exsanguinate" and add some more removal spells
"Vampire Hexmage" can be put into the sideboard. I now he is strong, but there are better vampires, e.g. a 4th "Bloodghast" or a 4th "Vampire Nighthawk".
I you have any free slots I would take a look at "Vampire Nocturnus" or "Bloodlord of Vaasgoth"
Perhaps change from "Grasp of Darkness" to "Tragic Slip"
I also would remove "Dreadship Reef" for some more swamps or searchlands. The Reef is very slow, and you don't need blue mana in any of your cards. Also it doesn't count for "Tendrils of Corruption"
As for the sideboard, I personally love "Evil Presence" as it can 'destroy' your opponents mana-base, especially if he uses duallands

Greetings
Muktol

For a token-heavy deck I would remove "Afflicted Deserter" (Sideboard) and "Scorned Villager" (Do some testgames, but I feel that the additional ramp won't be missed). Use the free slots to increase the number of "Mayor of Avabruck" to 4.
With the remaining slots I would either use some more protection, e.g. "Vines of Vastwood", something to push your creatures e.g. "Instigator Gang" or some removals, e.g. "Lightning Bolt" or "Searing Blaze"

Greetings
Muktol