The original inspiration for this deck came from a primer I found on the MTG Salvation forums. You can and should read it here: http://www.mtgsalvation.com/forums/the-game/modern/deck-creation-modern/554956-ritual-gifts. That should help explain the gameplan of the deck and the basic ideas behind most of the cards.
I found the list too be a little bit unrefined. Even though I've seen it claimed that the combo was lightweight, really there were ~13 nonland cards that were practically dead outside of the combo and/or would not effect the board state. Compare that to IE scapeshift which has something around 4 dead cards (Scapeshift itself) and is trying to play the same sort of control/combo game.
Overall this made the consistency of the deck pretty bad. A deck with 25 lands and 13 dead cards generates a lot of games where you only get to play 1 or 2 cards to control anything.
Most of the changes I made, then, were focused around trying to make the gameplan of the deck more consistent. Some notables that are different from other lists:
Mystic retrieval - Other versions of this deck run 2x past in flames and use noxious retrieval to move grapeshot out of the graveyard to let you remand it for the combo. This caused a few problems with the deck. First, noxious revival is probably one of the worst culprits of cards that are really bad to draw outside of the combo. Running Mystic retrieval over revival also means that you don't need manamorphose to draw into grapeshot after revival puts it on top of your library. So running retrieval over past in flames effectively cuts two cards.
I also cut desperate ritual. You don't need desperate and pyretic rituals for the combo. The only real problem with cutting one or the other is that you actually usually need to draw into some card of the combo before you can go off (because going for the combo gifts pile and getting handed past in flames and increasing vengeance without something in hand makes combing hard without lots of land). The thing is that if you still have 5 cards you can draw into that makes that pile much more comfortable. With that and Augur it is actually very rare that you don't have what you need.
Eternal Witness - Witness effectively grants the potential for another game plan. At seven mana, you can play eternal witness returning cryptic command from your graveyard, then you can cast cryptic command to bounce your witness and do something else, and do that every turn to create a "soft lock." Witness can also sometimes be used to return combo pieces to your hand if you end up using them outside of the combo.
SIDEBOARD:
Life from the Loam - used to create a gifts pile against control that is this + tech edge, allowing you to often prevent them from playing beyond 4 lands, which is pretty hard for some decks to beat
Baloth - BG/x can be a bad matchup, and Baloth helps a bit to help shore it up. Burn is also potentially extremely bad and baloth is a real "lifesaver."
