TheSwarmer

Harsh Sustenance is not really fitting as a playset, 3 or 2 of would be better. The main reason is the fact that it requires creatures so it never goes out on curve and ends up doing nothing for a few turns when if it was some other spell you would play it. I would replace 1 Sustenance with Unmake and 1 more with Glorious Anthem or something else of your choice, Souls of the Faultless for example.
Through I would cut it completly.
Replace Doomed Traveler with vault skirge or Mourning Thrull, they make more sence in your deck imo. The traveler is more of an aggro/token card while the lifelinkers are midrange cards, your deck is a midrange deck at heart, through the enchantments give it a really nice twist,plus I'm really into black enchantments.
Sin collector and blind hunter can work in this deck. Not the best ones through.
If you go with one or the other I think adding 1 more mimic is a good idea, he can work EXTREMELY well in certain decks.

Besides that this deck is really good, like really really good for someone who has 3 weeks of experience.
The thing I would do if I owned it would be cutting 4 Harsh Sustenance in favor of 1 obzedat, 1 unmake, 1 mimic and 1 Souls of the Faultless. And 3 Doomed Traveler for 3 Mourning Thrull or vault skirge. And that is what I recommend you do.
That would make it fully focused on 1 thing, consistant and both capeable of winning instantly and playing a slow grindy game. And would just turn it into something really well built.

Now for the sb, you built in nicely, it has graveyard hate, combo/control distrubtion, more threats and Exquisite Blood.
The only thing I don't like is Zealous Persecution, maybe it works for you idk but 1 more Castigate, and some enchantment destruction like disenchant or demistify as a 2 of would be better.

BTW many of my descriptions are super outdated. I often change my decks but don't change the description

You can't pay life when at 0 or less life cause there is nothing to pay with.
BTW gutshot was there vs lotus cobra, decks that run swords, or any annoying 1 hp dudes.

First decide in which way you want to build, here are mine:
http://www.mtgvault.com/theswarmer/decks/budget-black-white-tokens/
http://www.mtgvault.com/theswarmer/decks/budget-new-extort/
http://www.mtgvault.com/theswarmer/decks/budget-halloween-lifedrain/
http://www.mtgvault.com/theswarmer/decks/budget-orzhov-midrange/
http://www.mtgvault.com/theswarmer/decks/budget-good-old-orzhov/
http://www.mtgvault.com/theswarmer/decks/extort-thingy/
http://www.mtgvault.com/theswarmer/decks/budget-warriors/

These are just some of the directions you can go in. If you want I can build a control deck for you. Black white control uses expensive spells and enchantments to win and kill spells and distrubtion to stall.

Also for bloodgift demon. He is better than Indulgent Tormentor for a few reasons:

1 more thoughtness , staying out of the range of lightning bolt is very good, but that depends on the people you play with, if they don't have lightning bolt or lightning strike Indulgent Tormentor is better.

With Indulgent Tormentor you never get what you want(just as with dash hopes) when they have 40 life they will pay life, if they have 10 saproling tokens they will sac a creature. Through this can be a big upside of Indulgent Tormentor, especially if you don't run into players willing to pay life or creatures. If that is your case keep on using him. 4 of him, if you can.
Also 1 life per card is a great exchange, especially in your deck with obzedat and the siege. Much better than Sign in blood for example

That aside, if you want I could copy your deck and try to polish it, and looking at your deck I think it comes the closest to a midrange deck. The planeswalkers, lingering souls, the siege, Obzedat. All those can be found in midrange decks.
Also Mortify is something to look at.
But as I said try to choose a strategy, currently most b/w strategies would allow you to keep about 12 cards plus all your planeswalkers and most of your mana base.
Oh and for duress. Yes it would be worthed. Most decks of your kind run 4 Castigate but duress is fine too.
For triplicate spirits you can try midnight haunting, Belfry Spirit, Spectral Procession.
If you want to go palace siege and more black enchantments i recomend you start building your deck like a control deck. That means A LOT of stuff for black white decks. And if you do try Sorin's revenge.

PS: I am not you so if I start talking bullshit forgive me, I'm just judging on my experience with both competitive and casual mtg.

It seems a little unfocused. You want your deck to focus on 1 goal(beside winning)
First of all you need to know what you want to build into.
A midrange deck(get value with everything while killing their stuff and distrubting them)
A token deck(tokens, distrubtion enchantments that pump your guys)
B/W also allows for an extort deck, extort reads: Extort (Whenever you cast a spell, you may pay 1 hybrid black/white mana. If you do, each opponent loses 1 life and you gain that much life.)
if you choose GENERAL SUGGESTIONS:
Bloodgift demon is a really good card, better than Indulgent Tormentor, I would try to get 4 of him
Obzedat, ghost council is also good but a bit higher in price
Don't run Dash Hopes2x, you never get what you want. unless you are a mono black aggressive deck.

If you want I can link you some of my decks in b/w.

PS: This deck is about 300% more complete and normal than any other deck posted by someone new to the game.
Writing on my phone

That is a good idea, do you think that removing a gut shot or 2 for phyrexian unlife would work? the rest of the sb is too important to change.

I cut a Moltensteel Dragon.
With the draw sample hand tool I saw that usually it is harder to cast than panther and does less than Urabrask.
I really want to make this in real life, it just looks soo sweet.

Pls someone tell me what to cut here:
http://www.mtgvault.com/theswarmer/decks/budget-phyrexian-mana/ I think it needs everything in there.

My brother would sell his kidney to play with Progenitus :)
Great deck man, really like it.

For all you interested this is my deck now: http://www.mtgvault.com/theswarmer/decks/budget-gb-fungus/
And here is a precise guide on how to build a fungus deck, anyone who knows some valid information on the matter pls put suggestions into the comments: http://www.mtgvault.com/theswarmer/decks/how-to-build-a-fungus-deck/

But what to cut. . .
Some of the removal and add the sliver that destroys arifacts or enchantments when he enters...... maybe?

I am so dumb, Tidehollow Sculler! Epochrasite, how could I forget about Epochrasite

Dude pls, some good early game artifacts for Dispatch.

Sphinx's Revelation is 6 bucks, :(
This deck will take me some time, not sure how I want to build it. I want metalcraft and artifact win cons but there is so much more I would love to fit in.

Thanks, added it to the sb. It would do really well vs removal.

Added 1, you don't have enough stuff that goes into the grave to justify running more.
Jace's Ingenuity does just fine, if it ran fetches i would SOOOOOOOOO play trasure cruise

Added think twice

dont have the cards, nor the money :(
But a really good challange, probably could beat all my friends with this one through :D

http://www.mtgvault.com/northernwarlord/decks/budget-decks-mini-minotaur/
or
http://www.mtgvault.com/northernwarlord/decks/budget-decks-minotaur/

what? who?