Reanimation lunacy

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