Jolrael, Empress of Beasts+Shields of Velis Vel+Tivadars Crusade

Use jolrael to make all of an opponents lands creatures, make those changelings with Shields of Velis Vel, then destroy those lands with Tivadars Crusade

Krark Clan Ironworks+Grinding Station+Genesis Chamber+2x Myr Retriever

Sacrifice a Myr Retriever to Krark Clan Ironworks, then sacrifice the other to Grinding Station, and return the first to your hand. But when you played the Myr Retreivers you got two 1/1's, both of which you can sacrifice to Krark Ironworks, getting the mana for the myr retrievers. Repeat until opponent has no cards left in his/her library.

Tivadars Crusade+Shields of Velis Vel

Make all of your opponents creatures changelings, then wipe the board with Tivadars Crusade

Tivadars Crusade+Standardize+Mistform Wakcaster

Play standardize, choosing goblins, then use Mistform Wakcaster to make all your creatures something else, and finally play Tivadars Crusade to wipe the board

Melira, Sylvok Outcast+Devoted Druid

Infinite mana.

Sliver Queen+Ashnods Altar+Heartstone

Continually sacrifice slivers for infinite mana

Sliver Queen+Mana Echos

Sliver Queen counts as a sliver, so pretty soon you can have infinite mana.

Basalt Monolith+Power Artifact

Infinite mana! Add fireball for the win.

Angelic Renewal+Sun Titan+Bloodflow Connoisseur

Same as previous post, but instead of sacrificing to Altar of Dementia you are sacrificing to Bloodflow Connoisseur.

Angelic Renewal+Sun Titan+Altar of Dementia

Sacrifice Sun Titan to Altar of Dementia, bury Angelic Renewal to bring back Sun Titan, use Sun Titans ability to bring back Angelic Renwal, repeat.

Presence of Gond+Intruder Alarm

Enchant a creature with Presence of Gond:Infinite Wolves

Archangel of Thrune+Spike Feeder

Constantly removing the +1/+1 counters from Spike Feeder to gain life and put more +1/+1 counters on all creatures.

Animate Land+Eradicate

If you animate an opponents land with Animate Land, then exile that land with Eradicate you exile all of those lands from their hand, graveyard and library, and they have to make do with what they have on the battle field.

Melira,Sylvok Outcast+Bloodflow Connoiseur+Kitchen Finks

You can infinitely gain 2 life and boost Bloodflow Connesuir infinitely by constantly sacrificing Kitchen Finks

Urborg,Tomb of Yawgmoth+Cabal Coffers or Nightmare or Squelching Leeches or Quag Sickness

Using urborg, which makes all your lands swaps, for two mana you can double all the mana available to you, with cabal coffers. With quag sickness or nightmare/squelching leeches, you can have a powerful creature and good creature removal.

Sanguine Bond+Exquisite Blood+Any Damage (Touch of Death)

These two cards deals literally infinite damage and gains you infinite life

The touch of death just as a placeholder for a damage spell

Krenko, mob boss + intruder alarm

This great combo gives you as many 1/1 goblins as you want.